U.S. patent application number 16/540996 was filed with the patent office on 2020-11-12 for power transmission apparatus for hybrid electric vehicle.
This patent application is currently assigned to Hyundai Motor Company. The applicant listed for this patent is Hyundai Motor Company, Kia Motors Corporation. Invention is credited to Woo Jin CHANG, Wonmin CHO, Seong Wook HWANG, Seongwook JI, Chon Ok KIM, KiTae KIM, Juhyeon PARK, Yong Uk SHIN, Woochurl SON, llhan YOO.
Application Number | 20200353809 16/540996 |
Document ID | / |
Family ID | 1000004275897 |
Filed Date | 2020-11-12 |
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United States Patent
Application |
20200353809 |
Kind Code |
A1 |
PARK; Juhyeon ; et
al. |
November 12, 2020 |
POWER TRANSMISSION APPARATUS FOR HYBRID ELECTRIC VEHICLE
Abstract
A power transmission apparatus may include a motor/generator
having a rotor selectively connectable to an engine output shaft, a
first input shaft mounted along an axis of the engine output shaft
and fixedly connected to the rotor, a second input shaft external
and selectively connectable to the first input shaft, first and
second intermediate shafts and an output shaft mounted in parallel
with the input shafts, a planetary gear set mounted on the output
shaft, having a sun gear fixedly connected to the output shaft,
selectively receiving torques from the first and second input
shafts and the first and second intermediate shafts, and outputting
the shifted torque based on the received torques to the output
shaft, and a plurality of gear sets allowing torque flows between
the first and second input shafts, the first and second
intermediate shafts, and the output shaft.
Inventors: |
PARK; Juhyeon;
(Uiryeong-Eup, KR) ; SHIN; Yong Uk; (Suwon-Si,
KR) ; JI; Seongwook; (Gunpo-Si, KR) ; KIM;
KiTae; (lncheon, KR) ; SON; Woochurl;
(Seongnam-Si, KR) ; CHO; Wonmin; (Hwaseong-Si,
KR) ; YOO; llhan; (Hwaseong-Si, KR) ; CHANG;
Woo Jin; (Suwon-Si, KR) ; HWANG; Seong Wook;
(Gunpo-Si, KR) ; KIM; Chon Ok; (Yongin-Si,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company
Kia Motors Corporation |
Seoul
Seoul |
|
KR
KR |
|
|
Assignee: |
Hyundai Motor Company
Seoul
KR
Kia Motors Corporation
Seoul
KR
|
Family ID: |
1000004275897 |
Appl. No.: |
16/540996 |
Filed: |
August 14, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60K 6/365 20130101;
B60W 10/113 20130101; F16H 37/046 20130101; B60K 6/26 20130101;
F16H 3/002 20130101 |
International
Class: |
B60K 6/365 20060101
B60K006/365; F16H 37/04 20060101 F16H037/04; B60K 6/26 20060101
B60K006/26; F16H 3/00 20060101 F16H003/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 8, 2019 |
KR |
10-2019-0053471 |
Claims
1. A power transmission apparatus for a hybrid vehicle, the power
transmission apparatus comprising: a motor/generator having a rotor
selectively connectable to an engine output shaft fixedly connected
to an engine; a first input shaft mounted coaxial with the engine
output shaft and fixedly connected to the rotor; a second input
shaft formed as a hollow shaft mounted coaxial with and external to
the first input shaft, and selectively connectable to the first
input shaft; first and second intermediate shafts mounted in
parallel with the first input shaft; an output shaft mounted in
parallel with the first and second input shafts and outputting a
shifted torque; a planetary gear set mounted on the output shaft,
having a first rotation element fixedly connected to the output
shaft, selectively receiving torques from the first and second
input shafts and the first and second intermediate shafts, and
outputting the shifted torque based on the received torques to the
output shaft; and a plurality of gear sets, each of which allows at
least one torque flow between the first and second input shafts,
the first and second intermediate shafts, and the output shaft.
2. The power transmission apparatus of claim 1, wherein the
plurality of gear sets include: a first gear set including a first
input gear, a first gear, and a second gear, the first input gear
being fixedly connected to the first input shaft, the first gear
being rotatably mounted on and selectively connectable to the first
intermediate shaft and gear-engaged with the first input gear, the
second gear being rotatably mounted on the output shaft,
gear-engaged with the first input gear, and selectively connectable
to a second rotation element of the planetary gear set; a second
gear set including a second shifting gear, a third gear, and a
fourth gear, the second shifting gear being rotatably mounted on
the second input shaft and selectively connectable to the second
input shaft, the third gear being rotatably mounted on the output
shaft, gear-engaged with the second shifting gear, fixedly
connected to a third rotation element of the planetary gear set,
and selectively connectable to the output shaft, the fourth gear
being fixedly connected to the second intermediate shaft and
gear-engaged with the third gear; and a third gear set including a
first shifting gear and a fifth gear, the first shifting gear being
rotatably mounted on the first intermediate shaft and selectively
connectable to the first intermediate shaft, the fifth gear being
fixedly connected to the second intermediate shaft and gear-engaged
with the first shifting gear.
3. The power transmission apparatus of claim 2, wherein the first,
second and third rotation elements are a sun gear, a planet carrier
and a ring gear, respectively, wherein the first shifting gear is
selectively connectable to the first intermediate shaft by a first
synchronizer; and wherein the second shifting gear is selectively
connectable to the second input shaft by a second synchronizer.
4. The power transmission apparatus of claim 2, wherein the
planetary gear set is formed as a single pinion planetary gear
set.
5. The power transmission apparatus of claim 2, further including
five clutches, each of which selectively allows the at least one
torque flow between the first and second input shafts, the first
and second intermediate shafts, and the output shaft.
6. The power transmission apparatus of claim 5, wherein the five
clutches include: an engine clutch mounted between the engine
output shaft and the first input shaft; a first clutch mounted
between the first input shaft and the second input shaft; a second
clutch mounted between the first gear and the first intermediate
shaft; a third clutch mounted between the second gear and the
second rotation element; and a fourth clutch mounted between the
third gear and the output shaft.
7. The power transmission apparatus of claim 6, wherein the fourth
clutch is formed as a teeth engagement clutch.
8. The power transmission apparatus of claim 1, wherein the
plurality of gear sets include: a first gear set including a first
input gear, a first gear, and a second gear, the first input gear
being fixedly connected to the first input shaft, the first gear
being rotatably mounted on and selectively connectable to the first
intermediate shaft and gear-engaged with the first input gear, the
second gear being rotatably mounted on the output shaft,
gear-engaged with the first input gear, and selectively connectable
to a second rotation element of the planetary gear set; a second
gear set including a second shifting gear, a third gear, and a
fourth gear, the second shifting gear being rotatably mounted on
the second input shaft and selectively connectable to the second
input shaft, the third gear being rotatably mounted on the output
shaft, gear-engaged with the second shifting gear, fixedly
connected to a third rotation element of the planetary gear set,
and selectively connectable to the output shaft, the fourth gear
being fixedly connected to the second intermediate shaft and
gear-engaged with the third gear; a third gear set including a
first shifting gear and a fifth gear, the first shifting gear being
rotatably mounted on the first intermediate shaft and selectively
connectable to the first intermediate shaft, the fifth gear being
fixedly connected to the second intermediate shaft and gear-engaged
with the first shifting gear; and a fourth gear set including a
third shifting gear and a sixth gear, the third shifting gear being
rotatably mounted on the first intermediate shaft and selectively
connectable to the first intermediate shaft, the sixth gear being
fixedly connected to the second intermediate shaft and gear-engaged
with the third shifting gear.
9. The power transmission apparatus of claim 8, wherein the first,
second and third rotation elements are a sun gear, a planet carrier
and a ring gear, respectively, wherein the first shifting gear and
the third shifting gear are selectively connectable by a first
synchronizer; and wherein the second shifting gear is selectively
connectable to the second input shaft by a second synchronizer.
10. The power transmission apparatus of claim 8, wherein the
planetary gear set is formed as a single pinion planetary gear
set.
11. The power transmission apparatus of claim 8, further including
five clutches each of which allows the at least one torque flow
between the first and second input shafts, the first and second
intermediate shafts, and the output shaft.
12. The power transmission apparatus of claim 11, wherein the five
clutches comprise: an engine clutch mounted between the engine
output shaft and the first input shaft; a first clutch mounted
between the first input shaft and the second input shaft; a second
clutch mounted between the first gear and the first intermediate
shaft; a third clutch mounted between the second gear and the
second rotation element; and a fourth clutch mounted between the
third gear and the output shaft.
13. The power transmission apparatus of claim 12, wherein the
fourth clutch is formed as a teeth engagement clutch.
14. The power transmission apparatus of claim 1, further including
a parking shaft mounted in parallel with the output shaft, wherein
a seventh gear gear-engaged with a final reduction gear is fixedly
connected to the parking shaft, and wherein a parking gear is
fixedly connected to the parking shaft.
15. The power transmission apparatus of claim 14, wherein the
plurality of gear sets include: a first gear set including a first
input gear, a first gear, and a second gear, the first input gear
being fixedly connected to the first input shaft, the first gear
being rotatably mounted on and selectively connectable to the first
intermediate shaft and gear-engaged with the first input gear, the
second gear being rotatably mounted on the output shaft,
gear-engaged with the first input gear, and selectively connectable
to a second rotation element of the planetary gear set; a second
gear set including a second shifting gear, a third gear, a fourth
gear, and the braking gear, the second shifting gear being
rotatably mounted on the second input shaft and selectively
connectable to the second input shaft, the third gear being
rotatably mounted on the output shaft, gear-engaged with the second
shifting gear, fixedly connected to a third rotation element of the
planetary gear set, and selectively connectable to the output
shaft, the fourth gear being fixedly connected to the second
intermediate shaft and gear-engaged with the third gear, the
braking gear rotatably being mounted on the parking shaft,
gear-engaged with the third gear, and selectively connectable to a
transmission housing; a third gear set including a first shifting
gear and a fifth gear, the first shifting gear being rotatably
mounted on the first intermediate shaft and selectively connectable
to the first intermediate shaft, the fifth gear being fixedly
connected to the second intermediate shaft and gear-engaged with
the first shifting gear; and a fourth gear set including a third
shifting gear and a sixth gear, the third shifting gear being
rotatably mounted on the first intermediate shaft and selectively
connectable to the first intermediate shaft, the sixth gear being
fixedly connected to the second intermediate shaft and gear-engaged
with the third shifting gear.
16. The power transmission apparatus of claim 15, wherein the
first, second and third rotation elements are a sun gear, a planet
carrier and a ring gear, respectively, wherein the first shifting
gear and the third shifting gear are selectively connectable by a
first synchronizer; and wherein the second shifting gear is
selectively connectable to the second input shaft by a second
synchronizer.
17. The power transmission apparatus of claim 15, wherein the
planetary gear set is formed as a single pinion planetary gear
set.
18. The power transmission apparatus of claim 15, further
including: five clutches, each of which selectively allows the at
least one torque flow between the first and second input shafts,
the first and second intermediate shafts, and the output shaft; and
a brake selectively connecting the third rotation element to the
transmission housing.
19. The power transmission apparatus of claim 18, wherein the five
clutches include: an engine clutch mounted between the engine
output shaft and the first input shaft; a first clutch mounted
between the first input shaft and the second input shaft; a second
clutch mounted between the first gear and the first intermediate
shaft; a third clutch mounted between the second gear and the
second rotation element; and a fourth clutch mounted between the
third gear and the output shaft, and wherein the brake is mounted
between the braking gear and the transmission housing.
20. The power transmission apparatus of claim 19, wherein the
fourth clutch is formed as a teeth engagement clutch.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to Korean Patent
Application No. 10-2019-0053471 filed on May 8, 2019, the entire
contents of which is incorporated herein for all purposes by this
reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a power transmission
apparatus according to a hybrid vehicle.
Description of Related Art
[0003] An environmentally-friendly technology of a vehicle is a
core technology which controls survival of a future vehicle
industry, and advanced vehicle makers have focused their energy on
the development of an environmentally-friendly vehicle to achieve
environmental and fuel efficiency regulations.
[0004] An electric vehicle (EV) or a hybrid electric vehicle (HEV)
that utilizes electrical energy, or a double clutch transmission
(DCT) improving efficiency and convenience of a transmission may be
examples of such a future vehicle technology.
[0005] The double clutch transmission (DCT) includes two clutches
devices and a gear train of a basically manual transmission,
selectively transmits a torque input from an engine to two input
shafts by use of the two clutches devices, and outputs a torque
shifted by the gear train.
[0006] Such a double clutch transmission (DCT) attempts to
compactly realize a multi-stage transmission of more than five
speeds. The dual-clutch transmission (DCT) achieves an automated
manual transmission (AMT) that removes the inconvenience of a
manual shifting of a driver, by controlling two clutches and
synchronizing devices by a controller.
[0007] In comparison with an automatic transmission using planetary
gears, such a dual-clutch transmission (DCT) shows merits, such as
higher efficiency in power delivery, easier modification in
revising or adding parts to achieve more shifting stages, etc., and
thus gathers more spotlight since it can more comfortably conform
to fuel consumption regulation and efficiency in achieving more
shifting stages.
[0008] The information included in this Background of the Invention
section is only for enhancement of understanding of the general
background of the invention and may not be taken as an
acknowledgement or any form of suggestion that this information
forms the prior art already known to a person skilled in the
art.
BRIEF SUMMARY
[0009] Various aspects of the present invention are directed to
providing an exemplary power transmission apparatus for a vehicle
for a hybrid vehicle which may include a motor/generator having a
rotor selectively connectable to an engine output shaft, a first
input shaft mounted coaxial with the engine output shaft and
fixedly connected to the rotor, a second input shaft formed as a
hollow shaft mounted coaxial with and external to the first input
shaft, and selectively connectable to the first input shaft, first
and second intermediate shafts mounted in parallel with the first
input shaft, respectively, an output shaft mounted in parallel with
the first and second input shafts and outputting a shifted torque,
a planetary gear set mounted on the output shaft, having a sun gear
fixedly connected to the output shaft, selectively receiving
torques from the first and second input shafts and the first and
second intermediate shafts, and outputting the shifted torque based
on the received torques to the output shaft, and a plurality of
gear sets, each of which allows at least one torque flow between
the first and second input shafts, the first and second
intermediate shafts, and the output shaft.
[0010] The plurality of gear sets may include first to third gear
sets. The first gear set may include a first input gear, a first
external gear, and a second external gear, the first input gear
being fixedly connected to the first input shaft, the first
external gear being rotatably mounted on and selectively
connectable to the first intermediate shaft and externally
gear-meshed with the first input gear, the second external gear
being rotatably mounted on the output shaft, externally gear-meshed
with the first input gear, and selectively connectable to a planet
carrier of the planetary gear set. The second gear set may include
a second shifting gear, a third external gear, and a fourth
external gear, the second shifting gear being rotatably mounted on
the second input shaft and selectively connectable to the second
input shaft, the third external gear being rotatably mounted on the
output shaft, externally gear-meshed with the second shifting gear,
fixedly connected to a ring gear of the planetary gear set, and
selectively connectable to the output shaft, the fourth external
gear being fixedly connected to the second intermediate shaft and
externally gear-meshed with the third external gear. The third gear
set may include a first shifting gear and a fifth external gear,
the first shifting gear being rotatably mounted on the first
intermediate shaft and selectively connectable to the first
intermediate shaft, the fifth external gear being fixedly connected
to the second intermediate shaft and externally gear-meshed with
the first shifting gear.
[0011] The first shifting gear may be selectively connectable to
the first intermediate shaft by a first synchronizer. The second
shifting gear may be selectively connectable to the second input
shaft by a second synchronizer.
[0012] The planetary gear set may be formed as a single pinion
planetary gear set.
[0013] An exemplary embodiment of the present invention may further
include five clutches each of which facilitating selective
connection. The five clutches may include an engine clutch mounted
between the engine output shaft and the first input shaft, a first
clutch mounted between the first input shaft and the second input
shaft, a second clutch mounted between the first external gear and
the first intermediate shaft, a third clutch mounted between the
second external gear and the planet carrier, and a fourth clutch
mounted between the third external gear and the output shaft.
[0014] The fourth clutch may be formed as a teeth engagement
clutch.
[0015] The plurality of gear sets may include first to fourth gear
sets. The first gear set may include a first input gear, a first
external gear, and a second external gear, the first input gear
being fixedly connected to the first input shaft, the first
external gear being rotatably mounted on and selectively
connectable to the first intermediate shaft and externally
gear-meshed with the first input gear, the second external gear
being rotatably mounted on the output shaft, externally gear-meshed
with the first input gear, and selectively connectable to a planet
carrier of the planetary gear set. The second gear set may include
a second shifting gear, a third external gear, and a fourth
external gear, the second shifting gear being rotatably mounted on
the second input shaft and selectively connectable to the second
input shaft, the third external gear being rotatably mounted on the
output shaft, externally gear-meshed with the second shifting gear,
fixedly connected to a ring gear of the planetary gear set, and
selectively connectable to the output shaft, the fourth external
gear being fixedly connected to the second intermediate shaft and
externally gear-meshed with the third external gear. The third gear
set may include a first shifting gear and a fifth external gear,
the first shifting gear being rotatably mounted on the first
intermediate shaft and selectively connectable to the first
intermediate shaft, the fifth external gear being fixedly connected
to the second intermediate shaft and externally gear-meshed with
the first shifting gear. The fourth gear set may include a third
shifting gear and a sixth external gear, the third shifting gear
being rotatably mounted on the first intermediate shaft and
selectively connectable to the first intermediate shaft, the sixth
external gear being fixedly connected to the second intermediate
shaft and externally gear-meshed with the third shifting gear.
[0016] The first shifting gear and the third shifting gear may be
selectively connectable by a first synchronizer. The second
shifting gear may be selectively connectable to the second input
shaft by a second synchronizer.
[0017] An exemplary embodiment of the present invention may further
include a parking shaft mounted in parallel with the output shaft,
wherein a seventh external gear externally gear-meshed with a final
reduction gear is fixedly connected to the parking shaft, and
wherein a parking gear is fixedly connected to the parking
shaft.
[0018] The plurality of gear sets may include first to fourth gear
sets. The first gear set may include a first input gear, a first
external gear, and a second external gear, the first input gear
being fixedly connected to the first input shaft, the first
external gear being rotatably mounted on and selectively
connectable to the first intermediate shaft and externally
gear-meshed with the first input gear, the second external gear
being rotatably mounted on the output shaft, externally gear-meshed
with the first input gear, and selectively connectable to a planet
carrier of the planetary gear set. The second gear set may include
a second shifting gear, a third external gear, a fourth external
gear, and a braking gear, the second shifting gear being rotatably
mounted on the second input shaft and selectively connectable to
the second input shaft, the third external gear being rotatably
mounted on the output shaft, externally gear-meshed with the second
shifting gear, fixedly connected to a ring gear of the planetary
gear set, and selectively connectable to the output shaft, the
fourth external gear being fixedly connected to the second
intermediate shaft and externally gear-meshed with the third
external gear, the braking gear rotatably being mounted on the
parking shaft, externally gear-meshed with the third external gear,
and selectively connectable to a transmission housing. The third
gear set may include a first shifting gear and a fifth external
gear, the first shifting gear being rotatably mounted on the first
intermediate shaft and selectively connectable to the first
intermediate shaft, the fifth external gear being fixedly connected
to the second intermediate shaft and externally gear-meshed with
the first shifting gear. The fourth gear set may include a third
shifting gear and a sixth external gear, the third shifting gear
being rotatably mounted on the first intermediate shaft and
selectively connectable to the first intermediate shaft, the sixth
external gear being fixedly connected to the second intermediate
shaft and externally gear-meshed with the third shifting gear.
[0019] The first shifting gear and the third shifting gear may be
selectively connectable by a first synchronizer. The second
shifting gear may be selectively connectable to the second input
shaft by a second synchronizer.
[0020] An exemplary embodiment of the present invention may further
include five clutches each of which facilitating selective
connection, and one brake selectively connecting a corresponding
element to the transmission housing.
[0021] The one brake may be mounted between the braking gear and
the transmission housing.
[0022] According to an exemplary embodiment of the present
invention, multiple shifting stages may be realized by applying a
planetary gear set to a dual clutch type transmission, and by
further employing a motor/generator, an electric vehicle mode and a
parallel hybrid mode may be realized to the multiple shifting
stages.
[0023] Therefore, an internal structure may be simplified, shifting
efficiency may be improved, and an overall weight may be decreased,
improving an installability and fuel consumption
characteristics.
[0024] Furthermore, by additionally employing a gear set GT4, the
third forward speed FD3 may be realized by three different schemes,
facilitating a better choice depending on driving circumstances. By
designing gear ratios of the first, second, and fourth gear sets
GT1, GT2, and GT4, seven forward shifting stages in total may be
achieved including three shifting stages between the second forward
speed FD2 and the fourth forward speed FD4.
[0025] Furthermore, the sixth forward speed FD6 may be additionally
realized by additionally employing a parking shaft PKS and a brake
BK.
[0026] Furthermore, effects which may be obtained or expected from
exemplary embodiments of the present invention are directly or
suggestively described in the following detailed description. That
is, various effects expected from exemplary embodiments of the
present invention will be described in the following detailed
description.
[0027] The methods and apparatuses of the present invention have
other features and advantages which will be apparent from or are
set forth in more detail in the accompanying drawings, which are
incorporated herein, and the following Detailed Description, which
together serve to explain certain principles of the present
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0029] FIG. 2 is a shifting operation chart for power transmission
apparatus configured for a hybrid vehicle according to various
exemplary embodiments of the present invention.
[0030] FIG. 3 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0031] FIG. 4 is a shifting operation chart for power transmission
apparatus configured for a hybrid vehicle according to various
exemplary embodiments of the present invention.
[0032] FIG. 5 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0033] FIG. 6 is a shifting operation chart for a power
transmission apparatus configured for a hybrid vehicle according to
various exemplary embodiments of the present invention.
[0034] It may be understood that the appended drawings are not
necessarily to scale, presenting a somewhat simplified
representation of various features illustrative of the basic
principles of the present invention. The specific design features
of the present invention as included herein, including, for
example, specific dimensions, orientations, locations, and shapes
will be determined in part by the particularly intended application
and use environment.
[0035] In the figures, reference numbers refer to the same or
equivalent portions of the present invention throughout the several
figures of the drawing.
DETAILED DESCRIPTION
[0036] Reference will now be made in detail to various embodiments
of the present invention(s), examples of which are illustrated in
the accompanying drawings and described below. While the
invention(s) will be described in conjunction with exemplary
embodiments of the present invention, it will be understood that
the present description is not intended to limit the invention(s)
to those exemplary embodiments. On the other hand, the invention(s)
is/are intended to cover not only the exemplary embodiments of the
present invention, but also various alternatives, modifications,
equivalents and other embodiments, which may be included within the
spirit and scope of the invention as defined by the appended
claims.
[0037] Exemplary embodiments of the present application will be
described more fully hereinafter with reference to the accompanying
drawings, in which exemplary embodiments of the invention are
shown. As those skilled in the art would realize, the described
embodiments may be modified in various different ways, all without
departing from the spirit or scope of the present invention.
[0038] The drawings and description are to be regarded as
illustrative in nature and not restrictive, and like reference
numerals designate like elements throughout the specification.
[0039] In the following description, dividing names of components
into first, second and the like is to divide the names because the
names of the components are the same as each other and an order
thereof is not particularly limited.
[0040] FIG. 1 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0041] Referring to FIG. 1, a power transmission apparatus
according to various exemplary embodiments of the present invention
shifts torques of power sources of an engine ENG and the
motor/generator MG, and includes first and second input shafts IS1
and IS2, first and second intermediate shafts CS1 and CS2, output
shaft OS, planetary gear set PG and a plurality of gear sets GT1,
GT2, and GT3.
[0042] A power source of the power transmission apparatus may be
various types of a known engine ENG, such as a gasoline engine or a
diesel engine.
[0043] The motor/generator MG may act as a motor and also as a
generator, and includes a stator ST and a rotor RT, where the
stator ST is fixed to the transmission housing H and the rotor RT
is rotatably supported within the stator ST.
[0044] The torques of the engine ENG and the motor/generator MG
transmitted to the first input shaft IS1 and the second input shaft
IS2 are shifted by the first to third gear sets GT1 to GT3 and a
planetary gear set PG into a plurality of shifting stages, and
outputted to an output shaft OS.
[0045] The first and second input shafts IS1 and IS2 are mounted on
a same axis, and the first and second intermediate shafts CS1 and
CS2 and the output shaft OS are mounted in parallel with the first
input shaft IS1.
[0046] The first input shaft IS1 is mounted along an axis of an
engine output shaft EOS, selectively connectable to the engine
output shaft EOS, and fixedly connected to the rotor RT of the
motor/generator MG.
[0047] That is, the first input shaft IS1 selectively receives the
torque of the engine ENG, and always receives the torque of the
motor/generator MG.
[0048] The second input shaft IS2 is formed as a hollow shaft and
mounted coaxial with and external to the first input shaft IS1
without rotational interference therebetween, and selectively
connectable to the first input shaft IS1 thereby selectively
receiving torques of the engine ENG and the motor/generator MG.
[0049] The motor/generator MG is mounted on an axis of the engine
output shaft EOS, fixedly connected to the first input shaft IS1,
and selectively connectable to the second input shaft IS2.
[0050] The first and second intermediate shafts CS1 and CS2 are
mounted in parallel with the first input shaft IS1 respectively,
and connected to each other through an external gear
engagement.
[0051] The output shaft OS is mounted in parallel with the first
input shaft IS1 and the first and second intermediate shafts CS1
and CS2. The output shaft receives a shifted torque from the first
and second input shafts through the first gear set GT1 to third
gear set GT3, and transmits the received torque to a differential
DIFF through an output gear OG and a final reduction gear FDG.
[0052] The planetary gear set PG is mounted on an axis of the
output shaft OS, and fixedly connected to the output shaft OS
through a first rotation element N1 (sun gear S). The planetary
gear set PG forms a shifted torque by combining the torques
selectively received from the first and second input shafts IS1 and
IS2 and the first and second intermediate shafts CS1 and CS2, and
outputs the shifted torque to the output shaft OS.
[0053] The planetary gear set PG is a single pinion planetary gear
set, and includes a sun gear S, a planet carrier PC rotatably
supporting a plurality of pinion gear P externally gear-meshed with
the sun gear S, and a ring gear R internally gear-meshed with the
plurality of pinion gear P. The sun gear S acts as a first rotation
element N1, the planet carrier PC acts as a second rotation
elements N2, and the ring gear R acts as a third rotation elements
N3, respectively of the planetary gear set PG.
[0054] The plurality of gear sets are mounted over the first and
second input shafts IS1 and IS2, the first and second intermediate
shafts CS1 and CS2, and the output shaft OS, and form multiple
shifted torques from the torques of the first and second input
shafts IS1 and IS2.
[0055] In more detail, the plurality of gear sets include first,
second, and third gear sets GT1, GT2, and GT3 that are mounted over
the first and second input shafts IS1 and IS2, the first and second
intermediate shafts CS1 and CS2, and the output shaft OS.
[0056] The first gear set GT1 includes a first input gear IG1, a
first external gear EG1, and a second external gear EG2. The first
input gear IG1 is fixedly connected to the first input shaft IS1.
The first external gear EG1 is rotatably mounted on the first
intermediate shaft CS1, externally gear-meshed with the first input
gear IG1, and selectively connectable to the first intermediate
shaft CS1. The second external gear EG2 is rotatably mounted on the
output shaft OS, externally gear-meshed with the first input gear
IG1, and selectively connectable to the planet carrier PC of the
planetary gear set PG.
[0057] The second gear set GT2 includes a second shifting gear SG2,
a third external gear EG3, and a fourth external gear EG4. The
second shifting gear SG2 is rotatably mounted on the second input
shaft IS2 and selectively connectable to the second input shaft
IS2. The third external gear EG3 is rotatably mounted on the output
shaft OS, externally gear-meshed with the second shifting gear SG2,
fixedly connected to the ring gear of the planetary gear set PG.
and selectively connectable to the output shaft OS. The fourth
external gear EG4 is fixedly connected to the second intermediate
shaft CS2 and externally gear-meshed with the third external gear
EG3.
[0058] The third gear set GT3 includes a first shifting gear SG1
and a fifth external gear EG5. The first shifting gear SG1 is
rotatably mounted on the first intermediate shaft CS1 and
selectively connectable to the first intermediate shaft CS1. The
fifth external gear EG5 is fixedly connected to the second
intermediate shaft CS2 and externally gear-meshed with the first
shifting gear SG1.
[0059] The planetary gear set PG is mounted between the first gear
set GT1 and the second gear set GT2, where the planet carrier PC is
selectively connectable to the second external gear EG2 of the
first gear set GT1, and the ring gear R is selectively connectable
to the third external gear EG3 of the second gear set GT2.
[0060] The first shifting gear SG1 is selectively connectable to
first intermediate shaft CS1 by the first synchronizer SN1.
[0061] The second shifting gear SG2 is selectively connectable to
second input shaft IS2 by the second synchronizer SN2.
[0062] Gear ratios of drive and driven gears of the first, second,
and third gear sets GT1, GT2, and GT3 may be appropriately set
according to desired feature of the transmission.
[0063] Furthermore, engagement elements of five clutches ECL, CL1,
CL2, CL3, and CL4 are mounted between rotation members such as
various shafts.
[0064] The engine clutch ECL is mounted between the engine output
shaft EOS and the first input shaft IS1, and selectively connects
the engine output shaft EOS and the first input shaft IS1,
controlling torque transmission therebetween.
[0065] The first clutch CL1 is mounted between the first input
shaft IS1 and the second input shaft IS2, and selectively connects
the first input shaft IS1 and the second input shaft IS2,
controlling torque transmission therebetween.
[0066] The second clutch CL2 is mounted between the first external
gear EG1 and the first intermediate shaft CS1, and selectively
connects the first external gear EG1 and the first intermediate
shaft CS1, controlling torque transmission therebetween.
[0067] The third clutch CL3 is mounted between the second external
gear EG2 and the planet carrier PC, and selectively connects the
second external gear EG2 and the planet carrier PC, controlling
torque transmission therebetween.
[0068] The fourth clutch CL4 is mounted between the third external
gear EG3 and the output shaft OS, and selectively connects the
third external gear EG3 and the output shaft OS, controlling torque
transmission therebetween.
[0069] The engagement elements of the engine clutch ECL and the
first, second, third, and fourth clutches C1, C2, C3, and C4 may be
realized as multi-plate hydraulic pressure friction devices that
are frictionally engaged by hydraulic pressure, however, it may not
be understood to be limited thereto, since various other
configuration that are electrically controllable may be
available.
[0070] In the disclosure, when two or more members are described to
be "fixedly connected", where the member may be any of a shaft, an
input shaft, an output shaft, a rotation member, and a transmission
housing, it means that the fixedly connected members always rotate
at a same speed. That is, rotation elements and/or shafts fixedly
interconnected rotate in a same rotating direction and at a same
rotation speed.
[0071] When two or more members are described to be "selectively
connectable" by an engagement element, it means that the
selectively connectable members rotate separately when the
engagement element is not engaged, and rotates at a same speed when
the engagement element is engaged. It may be understood that in the
case that a member is "selectively connectable" with a transmission
housing by an engagement element, the member may be stationary when
the engagement element is engaged.
[0072] In an example, the fourth clutch CL4 may be formed as a
teeth engagement clutch, which is also referred to as a dog clutch,
improving torque transmission efficiency to the output shaft OS,
and reducing a length of a transmission.
[0073] The first and second synchronizers SN1 and SN2 may be formed
as a known scheme, and first and second sleeves SLE1 and SLE2
applied to the first and second synchronizers SN1 and SN2 may be
operated by actuators which may be controlled by a transmission
control unit.
[0074] The plurality of gear sets may be mounted in an order of the
first, second, and third gear sets GT1, GT2, and GT3 from an
opposite side of the engine output shaft EOS.
[0075] FIG. 2 is a shifting operation chart for a power
transmission apparatus configured for a hybrid vehicle according to
various exemplary embodiments of the present invention, and the
power transmission apparatus according to various exemplary
embodiments performs shifting operation as follows.
[0076] [The First Forward Speed]
[0077] In the first forward speed FD1 in an engine mode, as shown
in FIG. 2, the first intermediate shaft CS1 and the first shifting
gear SG1 are synchronously interconnect by the operation of the
sleeve SLE1 of the first synchronizer SN1, and simultaneously, the
engine clutch ECL and the second and fourth clutches CL2 and CL4
are operated.
[0078] As a result, by the operation of the engine clutch ECL, the
second clutch CL2, and the first synchronizer SN1, the torque of
the engine ENG passes through the engine output shaft EOS, the
first input shaft IS1, the first gear set GT1, the first
intermediate shaft CS1, the third gear set GT3, the second
intermediate shaft CS2, and the second gear set GT2.
[0079] As such, the torque received at the second gear set GT2 is
transmitted to the differential DIFF through the output shaft OS by
the operation of the fourth clutch CL4, realizing the first forward
speed.
[0080] The first forward speed FD1 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0081] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the first forward speed FD1 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG. In the instant case, the reverse speed may be realized by
operating the motor/generator MG in a reverse direction
thereof.
[0082] The shifting operation for the first forward speed FD1 in
the electric vehicle mode (EV mode) may be the same as in the first
forward speed FD1 in the engine mode, which is therefore not
described in further detail.
[0083] [The Second Forward Speed]
[0084] In the second forward speed FD2 in an engine mode, as shown
in FIG. 2, the second input shaft IS2 and the second shifting gear
SG2 are synchronously interconnect by the operation of the sleeve
SLE2 of the second synchronizer SN2, and simultaneously, the engine
clutch ECL, first and fourth clutches CL1 and CL4 are operated.
[0085] As a result, by the operation of the engine clutch ECL, the
first clutch CL1, and the second synchronizer SN2, the torque of
the engine ENG passes through the engine output shaft EOS, the
second input shaft IS2, and the second gear set GT2.
[0086] As such, the torque received at the second gear set GT2 is
transmitted to the differential DIFF through the output shaft OS by
the operation of the fourth clutch CL4, realizing the second
forward speed.
[0087] The second forward speed FD2 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0088] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the second forward speed FD2 in an
electric vehicle mode (EV mode) by the driving torque of the
motor/generator MG.
[0089] The shifting operation for the second forward speed FD2 in
the electric vehicle mode (EV mode) may be the same as in the
second forward speed FD2 in the engine mode, which is therefore not
described in further detail.
[0090] [The Third Forward Speed]
[0091] In the third forward speed FD3 in an engine mode, as shown
in FIG. 2, the engine clutch ECL and the third and fourth clutches
CL3 and CL4 are simultaneously operated
[0092] As a result, by the operation of the engine clutch ECL and
the third clutch CL3, the torque of the engine ENG passes through
the engine output shaft EOS, the first input shaft IS1, and the
first gear set GT1, and is transmitted to the planet carrier PC of
the planetary gear set PG.
[0093] Furthermore, while the planetary gear set PG receives an
input torque through the planet carrier PC, the second gear set GT2
and the output shaft OS are interconnected by the operation of the
fourth clutch CL4. Therefore, the planetary gear set PG forms a
closed torque loop between the sun gear S and the ring gear R, and
outputs the torque of the planet carrier PC to the differential
DIFF through the output shaft OS, realizing the third forward speed
FD3.
[0094] The third forward speed FD3 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0095] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the third forward speed FD3 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0096] The shifting operation for the third forward speed FD3 in
the electric vehicle mode (EV mode) may be the same as in the third
forward speed FD3 in the engine mode, which is therefore not
described in further detail.
[0097] [The Fourth Forward Speed]
[0098] In the fourth forward speed FD4 in an engine mode, as shown
in FIG. 2, the second input shaft IS2 and the second shifting gear
SG2 are synchronously interconnect by the operation of the sleeve
SLE2 of the second synchronizer SN2, and simultaneously, the engine
clutch ECL, first and third clutches CL1 and CL3 are operated.
[0099] As a result, by the operation of the engine clutch ECL, the
first clutch CL1, and the second synchronizer SN2, the torque of
the engine ENG partially passes through the engine output shaft
EOS, the second input shaft IS2, and the second gear set GT2, and
is transmitted to the ring gear R of the planetary gear set PG.
[0100] Furthermore, by the operation of the engine clutch ECL and
the third clutch CL3, the torque of the engine ENG partially passes
though the engine output shaft EOS, the first input shaft IS1, and
the first gear set GT1, and is transmitted to the planet carrier PC
of the planetary gear set PG.
[0101] As such, the planetary gear set PG forms a shifted torque by
a rotation speed difference between the ring gear R and the planet
carrier PC, and outputs the shifted toque to the differential DIFF
through the output shaft OS fixedly connected to the sun gear S,
realizing the fourth forward speed FD4 in the engine mode.
[0102] The fourth forward speed FD4 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0103] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the fourth forward speed FD4 in an
electric vehicle mode (EV mode) by the driving torque of the
motor/generator MG.
[0104] The shifting operation for the fourth forward speed FD4 in
the electric vehicle mode (EV mode) may be the same as in the
fourth forward speed FD4 in the engine mode, which is therefore not
described in further detail.
[0105] [The Fifth Forward Speed]
[0106] In the fifth forward speed FD5 in an engine mode, as shown
in FIG. 2, the first intermediate shaft CS1 and the first shifting
gear SG1 are synchronously interconnect by the operation of the
sleeve SLE1 of the first synchronizer SN1, and simultaneously, the
engine clutch ECL, second and third clutches CL2 and CL3 are
operated.
[0107] As a result, by the operation of the engine clutch ECL, the
second clutch CL2, and the first synchronizer SN1, the torque of
the engine ENG partially passes through the engine output shaft
EOS, the first input shaft IS1, the first gear set GT1, the first
intermediate shaft CS1, the third gear set GT3, the second
intermediate shaft CS2, and the second gear set GT2, and is
transmitted to the ring gear R of the planetary gear set PG.
[0108] Furthermore, by the operation of the engine clutch ECL and
the third clutch CL3, the torque of the engine ENG partially passes
though the engine output shaft EOS, the first input shaft IS1, and
the first gear set GT1, and is transmitted to the planet carrier PC
of the planetary gear set PG.
[0109] As such, the planetary gear set PG forms a shifted torque by
a rotation speed difference between the ring gear R and the planet
carrier PC, and outputs the shifted toque to the differential DIFF
through the output shaft OS fixedly connected to the sun gear S,
realizing the fifth forward speed FD5 in the engine mode.
[0110] The fifth forward speed FD5 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0111] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the fifth forward speed FD5 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0112] The shifting operation for the fifth forward speed FD5 in
the electric vehicle mode (EV mode) may be the same as in the fifth
forward speed FD5 in the engine mode, which is therefore not
described in further detail.
[0113] FIG. 3 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0114] Referring to FIG. 3, a power transmission apparatus
according to various exemplary embodiments differ from the various
exemplary embodiments of FIG. 1 in that a fourth gear set GT4 is
further included over the first intermediate shaft CS1 and the
second intermediate shaft CS2, to realize various arrangement of
the third forward speed.
[0115] The fourth gear set GT4 includes a third shifting gear SG3
and a sixth external gear EG6. The third shifting gear SG3 is
rotatably mounted on the first intermediate shaft CS1 and
selectively connectable to the first intermediate shaft CS1. The
sixth external gear EG6 is fixedly connected to the second
intermediate shaft CS2 and externally gear-meshed with the third
shifting gear SG3.
[0116] As well as first shifting gear SG1, the third shifting gear
EG3 is selectively connectable to first intermediate shaft CS1 by
the first synchronizer SN1.
[0117] Such various exemplary embodiments in FIG. 3 of the present
invention differs from the various exemplary embodiments of FIG. 1
substantially in that the fourth gear set GT4 is further
included.
[0118] FIG. 4 is a shifting operation chart for a power
transmission apparatus configured for a hybrid vehicle according to
various exemplary embodiments of the present invention, and the
power transmission apparatus performs shifting operation as
follows.
[0119] The fourth gear set GT4 employed in the various exemplary
embodiments relates to realizing a different form of the third
forward speed FD3, and the different form of the third forward
speed is described in detail below with reference to FIG. 4.
[0120] [The Third Forward Speed]
[0121] In a first example of the third forward speed FD3 in the
engine mode, the engine clutch ECL and the third and fourth
clutches CL3 and CL4 are simultaneously operated, the same as in
the various exemplary embodiments. In a second example, the first
intermediate shaft CS1 and the third shifting gear SG3 are
synchronously interconnect by the sleeve SLE1 of the first
synchronizer SN1, and the engine clutch ECL and the second and
fourth clutches CL2 and CL4 are simultaneously operated. In a third
example, the first intermediate shaft CS1 and the third shifting
gear SG3 is synchronously interconnected by the sleeve SLE1 of the
first synchronizer SN1, and the engine clutch ECL and the second
and third clutches CL2 and CL3 are simultaneously operated.
[0122] In the first example, as in the various exemplary
embodiments of the present invention, by the operation of the
engine clutch ECL and the third clutch CL3, the torque of the
engine ENG passes through the engine output shaft EOS, the first
input shaft IS1, and the first gear set GT1, and is transmitted to
the planet carrier PC of the planetary gear set PG.
[0123] Furthermore, while the planetary gear set PG receives an
input torque through the planet carrier PC, the second gear set GT2
and the output shaft OS are interconnected by the operation of the
fourth clutch CL4. Therefore, the planetary gear set PG forms a
closed torque loop between the sun gear S and the ring gear R, and
outputs the torque of the planet carrier PC to the differential
DIFF through the output shaft OS, realizing the third forward speed
FD3.
[0124] The third forward speed FD3 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0125] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the third forward speed FD3 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0126] The shifting operation for the third forward speed FD3 in
the electric vehicle mode (EV mode) may be the same as in the third
forward speed FD3 in the engine mode, which is therefore not
described in further detail.
[0127] In the second example, by the operation of the engine clutch
ECL, the second clutch CL2, and the first synchronizer SN1, the
torque of the engine ENG passes through the engine output shaft
EOS, the first input shaft IS1, the first gear set GT1, the first
intermediate shaft CS1, the fourth gear set GT4, the torque0, and
the torque1, and is transmitted to the torque3 of the torque2.
[0128] Furthermore, while the planetary gear set PG receives an
input torque through the ring gear R, the second gear set GT2 and
the output shaft OS are interconnected by the operation of the
fourth clutch CL4. Therefore, the planetary gear set PG forms a
closed torque loop between the sun gear S and the ring gear R, and
outputs the torque of the planet carrier PC to the differential
DIFF through the output shaft OS, realizing the third forward speed
FD3 in the second example.
[0129] The third forward speed FD3 in the second example is
described in connection with a case where a vehicle is driven by
the torque of the engine ENG, however, the parallel hybrid mode may
also be available by merely additionally operating the
motor/generator MG to supply an assistant torque.
[0130] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the third forward speed FD3 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0131] The shifting operation for the third forward speed FD3 in
the electric vehicle mode (EV mode) may be the same as in the third
forward speed FD3 in the engine mode, which is therefore not
described in further detail.
[0132] In the third example, by the operation of the engine clutch
ECL, the second clutch CL2, and the first synchronizer SN1, the
torque of the engine ENG partially passes through the engine output
shaft EOS, the first input shaft IS1, the first gear set GT1, the
first intermediate shaft CS1, the fourth gear set GT4, the second
intermediate shaft CS2, and the second gear set GT2, and is
transmitted to the ring gear R of the planetary gear set PG.
[0133] Furthermore, by the operation of the engine clutch ECL and
the third clutch CL3, the torque of the engine ENG partially passes
though the engine output shaft EOS, the first input shaft IS1, and
the first gear set GT1, and is transmitted to the planet carrier PC
of the planetary gear set PG.
[0134] As such, the planetary gear set PG forms a shifted torque by
a rotation speed difference between the ring gear R and the planet
carrier PC, and outputs the shifted torque to the differential DIFF
through the output shaft OS fixedly connected to the sun gear S,
realizing the third forward speed FD3 in the third example.
[0135] The third forward speed FD3 in the third example is
described in connection with a case where a vehicle is driven by
the torque of the engine ENG, however, the parallel hybrid mode may
also be available by merely additionally operating the
motor/generator MG to supply an assistant torque.
[0136] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the third forward speed FD3 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0137] The shifting operation for the third forward speed FD3 in
the electric vehicle mode (EV mode) may be the same as in the third
forward speed FD3 in the engine mode, which is therefore not
described in further detail.
[0138] According to a power transmission apparatus according to
various exemplary embodiments of the present invention, three
forward shifting stages may be realized between the second forward
speed FD2 and the fourth forward speed FD4, where specific gear
ratios of the three shifting stages may depend on specific gear
ratios between the first to fourth gear sets GT1 to GT4. Thus,
seven forward shift-speeds in total may be achieved by the
exemplary embodiment of the present invention.
[0139] FIG. 5 is a schematic view of power transmission apparatus
configured for a hybrid vehicle according to various exemplary
embodiments of the present invention.
[0140] Referring to FIG. 5, in comparison with the various
exemplary embodiments of FIG. 3, a power transmission apparatus
according to various exemplary embodiments of FIG. 5 may further
include a parking shaft PKS mounted in parallel with the output
shaft OS. A seventh external gear EG7 externally gear-meshed with
the final reduction gear FDG is fixedly connected to the parking
shaft PKS, and a parking gear PKG is fixedly connected to the
parking shaft PKS.
[0141] A braking gear BG is rotatably mounted on the parking shaft
PKS and externally gear-meshed with the third external gear EG3 of
the second gear set GT2. The braking gear BG is selectively
connectable to the transmission housing H.
[0142] That is, the second gear set GT2 further includes the
braking gear BG in addition to the second shifting gear SG2, the
third external gear EG3, and the fourth external gear EG4 of the
various exemplary embodiments.
[0143] The braking gear BG is selectively connectable to the
transmission housing H through a brake BK. By the operation of the
brake BK, the ring gear of the planetary gear set PG may be stopped
through the braking gear BG and the third external gear EG3.
[0144] It is notable that the brake BK and the braking gear BG may
stop the ring gear R of the planetary gear set PG, and thus the
location of the brake BK and the braking gear BG may be altered if
the ring gear R may be stopped.
[0145] Such various exemplary embodiments of FIG. 5, differ from
the various exemplary embodiments of FIG. 3 substantially in that
the parking shaft PKS and the brake BK are further included.
[0146] FIG. 6 is a shifting operation chart for a power
transmission apparatus configured for a hybrid vehicle according to
various exemplary embodiments of the present invention, and the
power transmission apparatus may perform shifting operation as
follows.
[0147] The parking shaft PKS and the brake BK that are further
included in an exemplary embodiment of the present invention enable
the ring gear R of the planetary gear set PG to act as a fixed
element to further realize the sixth forward speed FD6. Thus, the
sixth forward speed FD6 is below described in detail with reference
to FIG. 6.
[0148] The first forward speed FD1 to the fifth forward speed FD5
may be realized the same as in the various exemplary
embodiments.
[0149] [The Sixth Forward Speed]
[0150] In the sixth forward speed FD6 in an engine mode, as shown
in FIG. 6, the engine clutch ECL and the third clutch CL3, brake BK
are simultaneously operated
[0151] As a result, by the operation of the engine clutch ECL and
the third clutch CL3, the torque of the engine ENG passes through
the engine output shaft EOS, the first input shaft IS1, and the
first gear set GT1, and is transmitted to the planet carrier PC of
the planetary gear set PG.
[0152] Furthermore, while the planetary gear set PG receives an
input torque through the planet carrier PC, the ring gear R of the
planetary gear set PG acts as a fixed element by the operation of
the brake BK. Thus, the planetary gear set PG outputs an increased
speed through the sun gear S to the differential DIFF, realizing
the sixth forward speed FD6.
[0153] The sixth forward speed FD6 is described in connection with
the engine mode where a vehicle is driven by the torque of the
engine ENG, however, the parallel hybrid mode may also be available
by merely additionally operating the motor/generator MG to supply
an assistant torque.
[0154] Furthermore, when the motor/generator MG is operated while
the engine clutch ECL is released and the engine ENG is stopped, a
vehicle may be driven in the sixth forward speed FD6 in an electric
vehicle mode (EV mode) by the driving torque of the motor/generator
MG.
[0155] The shifting operation for the sixth forward speed FD6 in
the electric vehicle mode (EV mode) may be the same as in the sixth
forward speed FD6 in the engine mode, which is therefore not
described in further detail.
[0156] As described above, according to an exemplary embodiment of
the present invention, multiple shifting stages may be realized by
applying a planetary gear set to a dual clutch type transmission,
and by further employing a motor/generator, an electric vehicle
mode and a parallel hybrid mode may be realized to the multiple
shifting stages.
[0157] Furthermore, by realizing multiple shifting stages while
simplifying internal structure, shifting efficiency may be improved
and an overall weight may be decreased, improving an installability
and fuel consumption characteristics.
[0158] Furthermore, an electric vehicle mode and a hybrid mode may
be realized by operating a motor/generator, improving fuel
consumption characteristics.
[0159] Furthermore, by additionally employing a gear set GT4, the
third forward speed FD3 may be realized by three different schemes,
facilitating a better choice depending on driving circumstances. By
designing gear ratios of the first, second, and fourth gear sets
GT1, GT2, and GT4, seven forward shifting stages in total may be
achieved including three shifting stages between the second forward
speed FD2 and the fourth forward speed FD4.
[0160] Furthermore, the sixth forward speed FD6 may be additionally
realized by additionally employing a parking shaft PKS and a brake
BK. BG
[0161] For convenience in explanation and accurate definition in
the appended claims, the terms "upper", "lower", "inner", "outer",
"up", "down", "upwards", "downwards", "front", "rear", "back",
"inside", "outside", "inwardly", "outwardly", "internal",
"external", "inner", "outer", "forwards", and "backwards" are used
to describe features of the exemplary embodiments with reference to
the positions of such features as displayed in the figures. It will
be further understood that the term "connect" or its derivatives
refer both to direct and indirect connection.
[0162] The foregoing descriptions of specific exemplary embodiments
of the present invention have been presented for purposes of
illustration and description. They are not intended to be
exhaustive or to limit the present invention to the precise forms
disclosed, and obviously many modifications and variations are
possible in light of the above teachings. The exemplary embodiments
were chosen and described to explain certain principles of the
present invention and their practical application, to enable others
skilled in the art to make and utilize various exemplary
embodiments of the present invention, as well as various
alternatives and modifications thereof. It is intended that the
scope of the present invention be defined by the Claims appended
hereto and their equivalents.
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