[001]
The embodiment
s
h
erein
generally
relate
t
o
power
transmission
unit
in vehicles
and more
particularly
,
to
a
range actuation
arrangement
in a power
transmission unit of a vehicle (tractor, constructional vehicle, off
-
road vehicle and
the like),
and a method for actuating at least one of a low range gear
(low range
5
driven gear)
, a medium range
ge
ar
(medium
range
drive gear)
and a high range
coupler (high range dog clutch/high range dog teeth) in
a
power transmission unit
of a vehicle
,
wherein the range actuation arrangement comprises
a
single
range
actuati
ng
gear
adapted
to facilitate actuation
(engagement)
of at least one of
a
low
ran
ge gear
(low range driven gear)
,
a medium range gear (
medium range
drive
10
gear
)
and
a
high range coupler (high range dog clutch
/ high range dog teeth
)
in
response to
the
movement of a shift fork to corresponding rang
e position
on
engagement
of a ran
ge lever adapted to be
shifted
(moved)
to corresponding range
position
,
where the
range lever of the
power transmission unit is provided with a
sequential
gate
shift pattern (L
—
N1
—
M
—
N2
—
H
, where L represents low range
15
positio
n, N
1
represents neutral range position, M represents medium range
position, N2 represents
another
neutral
range
position
and H represents high range
position
)
.
BACKGROUND
[002]
G
enerally,
a
power transmission unit
of
a vehicle
is used for
20
transmitting
power
from an engine or an electric motor to the wheels of the
vehicle for propelling the vehicle
.
Conventional power transmission unit
20 (as
shown in fig
.
21 to 24
)
in
vehicles such as tractors or other similar
vehicles
comprises a
range lever
(not shown)
,
a
shifter bush
(not shown)
, a shifter rod 22
(as shown in fig. 21 to 24)
, a shift fork 24
(as shown in fig. 21 to 24)
, a shifter
25
sleeve 26
(as shown in fig. 21 to 24)
, a range
intermediate
shaft 28
(as shown in
fig. 21)
, a range output shaft 30
(as shown in
fig. 21 to 24)
,
a
low range epicyclic
gear
train unit
32
(acts as low range gear
, as shown in fig. 21 to 24)
and may
include other standard components as present in
a
standard power transmission
3
/
51
unit
.
The range lever is connected to the shifter bush that i
s mounted to the shifter
rod 22 at a predetermined position. The
shift fork 24 is mounted to the shifter rod
22 at a predetermined position,
and the
lugs
(not shown)
of the shift fork 24 are
connected to the shifter sleeve 26
. The shifter sleeve 26 is
mo
vably connected to
the range output shaft 30
.
The shifter sleeve 26 includes a plurality of external
5
splines
26E
(as shown in fig. 21 and 22)
provided to an outer portion (outer
diameter) of the shifter slee
ve 26 at a predetermined position (can be consid
ered
as one end of the shifter sleeve 26) and a plurality of internal splines
(not shown)
provided to an inner portion (inner diameter) of the shifter sleeve 26 at a
predetermined position, where the plurality of internal splines and the plurality of
10
exter
nal splines
26E
(as shown in fig. 22)
of the shifter sleeve 26 are co
-
planar to
each other.
The range
intermediate
shaft 28 includes an integrated high range dog
clutch
28H
(high range dog teeth
, as shown in fig.22 to 24
)
at a predetermined
position
(can be considered as one end of the range
intermediate
shaft 28)
, where
the high range dog clutch 28H includes a plurality of external splines 28E
(as
15
shown in fig. 22)
corresponding to the plurality of internal splines of the shifter
sleeve 26
.
The low r
ange epicyclic gear train unit
32
is mounted
on
to
a
gear box
housing and meshed with
the
range
intermediate
shaft
28
.
The
low range epicyclic
gear train unit 32
includes a ring gear 32R
(as shown in fig.
21
, also called as
internal gear
)
,
a carrier 32C
(as
shown in fig. 21 to fig. 24)
,
a plurality of planet
20
gears
32G
(as shown in fig. 21)
, a sun gear
(not shown)
, a needle roller bearing
32N
(as shown in fig. 21)
, a plurality o
f
thrust washers 32W
(as shown in fig. 21)
,
an output member 32S
(as shown in fig.
21 to fig. 24
,
can be considered
as ring
gear
)
and may include other standard components as present in a standard
epicyclic gear train unit
.
The output member 32S
(ring gear)
is rotatably
25
connected to the carrier 32C of the low range epicyclic gear train
unit 32, where
the output member 32
C includes a plurality of internal splines
32I
(as shown in fig.
21)
corresponding to the plurality of external splines 26E of the shifter sleeve 26
.
The operation of the conventional power transmission unit 20 is as foll
ows.
When
the range lever is engaged by the driver (operator driving the vehicle) to shift
30
(move) the range lever from a neutral range position to a low range position, the
4
/
51
shifter bush moves from the neutral range position to the low range position
therei
n to move the shifter rod 22 along a predefined direction thereby moving the
shift fork 24 and the shifter sleeve 26 from the neutral range position to the low
range position
(as shown in fig. 23)
therein to move the plurality of external
splines 26E of th
e shifter sleeve 26
in a direction towards the output member 32S
5
(ring gear)
of the low range epicyclic gear train unit 32
to enable engagement of
the plurality of external splines 26E of the shifter sleeve 26
with corresponding
plurality of internal splin
es 32I of the output member 32S
(ring gear)
thereby
facilitating actuation (engagement) of the low range epicyclic gear
train
unit 32
(low range gear) to transfer the power
from the range
intermediate
shaft 28
to the
10
range output shaft 30
through the shift
er sleeve 26,
and the range output shaft 30
rotates at a low speed.
Now, when the range lever is engaged by the driver
(operator driving the vehicle) to shift (move) the range lever from the neutral
range position to a high range position, the shifter bus
h moves from the neutral
range position to the high range position therein to move the shifter rod 22 along a
15
predefined direction thereby moving the shift fork 24 and the shifter sleeve 26
from the neutral range position to the high range position
(as sho
wn in fig. 24)
in a
direction towards the high range dog clutch 28H of the range
intermediate
shaft 28
therein to enable engagement of the plurality of internal splines of the shifter
sleeve 26 with corresponding plurality of
external
splines
28E
of
the hi
gh range
20
dog clutch 28H
thereby facilitating actuation (engagement) of the
high range dog
clutch 28H
to transfer the power
from the range
intermediate
shaft 28
to the range
output shaft 30 through the shifter sleeve 26, and the range output shaft 30 rotate
s
at a
high
speed.
[003]
Therefore, the aforementioned conventional power transmission unit
25
20
is provided with low range (low speed and high
torque
) and high range (high
speed and low
torque
).
However,
the arrangement and method for enabling
medium range
functionality
(medium
speed and corresponding power
)
is not
present in the aforementioned conventional power transmission unit 20.
Further,
t
he low range epicyclic gear train
unit 32 in the aforementioned
conventional
30
power transmission unit 20 is
complex
in design
,
and
is difficult to assemble and
35
/
51
achieved
by
engag
ing
the range lever 114 to shift (move)
the range lever 114
from
the low range position (L) to the neutral range position (N) which in turn moves
the shifter bush 116 from the low range position (L) to the neutral range position
(N)
thereby moving the shifter rod 118 in the predefined direction along X
-
axis
therein
to move the shift
fork 120 and the range actuating
gear 10G from the low
5
range position (L) to the neutral range position (N) in a direction away
from the
low range driven gear 110 therein to enable dis
-
engagement of the plurality of
locking elements 10c
of the first portion 10F of the range actuating gear 10G with
corresponding plurality of locking elements 110L of the low range driven gear
110 thereby facilitating de
-
actuation (dis
-
engagement) of the low range driven
10
gear 110. Thereafter, the operator e
ngages the range lever 114 to shift (move) the
range lever 114 from the neutral range position (N) to the medium range position
(M) whic
h in turn moves the shifter bush 116 from the neutral range position (N)
to the medium range position (M) thereby moving
the shifter rod 118 in the
predefined direction along X
-
axis therein to move the shift
fork 120 and the range
15
actuating
gear 10G from the neutral range position (N) to the medium range
position (M) therein to enable engagement of the plurality of first lo
cking
elements 10a of the range actuating gear 10G with corresponding plurality of
locking elements 112L of the medium range drive gear 112 thereby facilitating
actuation (engagement)of the medium range drive gear 112
.
Now
,
when
the
20
operator desires to ac
tuate (engage) the high range (high range coupler 102H),
then the operator must
de
-
actuate (dis
-
engage) the medium range drive gear 112
therein to enable actuation of the high range coupler 102H
which is achieved by
engag
ing
the range lever 114 to shift (m
ove) the range lever 114 from the medium
range position (M) to another neutral range position (N2) which in turn moves the
25
shifter bush 116 from the medium range position (M) to another neutral range
position (N2) thereby moving the shifter rod 118 in the
predefined direction along
X
-
axis
therein to move the
shift
fork 120 and the range actuating
gear 10G from
the medium range position (M) to another neutral range position (N2) therein to
enable dis
-
engagement of the plurality of first locking elements 10a
of the range
30
actuating gear 10G with corresponding plurality of locking elements 112L of the
36
/
51
medium range drive gear 112 thereby facilitating de
-
actuation (dis
-
engagement)of
the medium range drive gear 112.
Thereafter, the operator engages the range
lever
114 to shift (move) the range lever 114 from another neutral range position
(N2) to the high range position (H) which in turn moves the shifter bush 116 from
another neutral range position (N2) to the high range position (H) thereby moving
5
the shifter rod
118 in the predefined direction along X
-
axis therein to
move the
shift
fork 120 and the range actuating
gear 10G from another neutral range
position (N2) to the high range position (H) in a direction towards the high range
coupler 102H therein to enable engagement of the plurality of second locking
elements 10b of the range actuating gear 10G with correspon
ding plurality of
10
locking elements 102L of the high range coupler 102H thereby facilitating
actuation of the high range coupler 102H.
[0056]
Therefore, a range actuation arrangement 100 and
a
method for
actuating at least one of a low range driven gear 110, a
m
edium range drive gear
112
and a high range coupler 102H in a power transmission unit 100
is provided
15
for
a vehicle
. Further, a sequential
gate
shift pattern
(L
—
N1
—
M
—
N2
—
H
,
where L represents low range position, N1 represents neutral range position, M
repr
esents medium range position, N2 represents
another
neutral
range position
and H represents high range position
)
is provided
for a range lever 114
to enable
actuation of at least one of a low range driven gear 110, a
medium range drive
20
gear 112
and a high
range coupler 102H in a power transmission unit 100
is
provided
.
[0057]
Th
e foregoing
description of the specific embodiments will so fully
reveal the general nature of the embodiments herein that others can, by applying
current knowledge, readily modify and/or adapt for various applications such
25
specific embodiments without departing from
the generic concept, and, therefore,
such adaptations and modifications should and are intended to be comprehended
within the meaning and range of equivalent
s of the disclosed embodiments.
It is
to be understood that the phraseology or terminology employ
ed herein is for the
purpose of des
cription and not of limitation.
Therefore, while the embodiments
30
herein have been described in terms of embodiments, those skilled in the art will
37
/
51
recognize that the embodiments herein can be practiced with modification
within
the spirit and scope of the embodiments as described herein

We claim,
1.
A
range actuation
arrangement
10
in
a
vehicle
power transmission
unit
10
0
comprising a low range driven gear 110 defining a plurality of
locking elements 110L, a
medium range drive gear 112
defining a plurality
of locking elements 112L
,
a shift fork
120
,
and a range input shaft 102
having a high range coupler 102
H
defining a plu
rality of
locking elements
102L
, said
range actuation
arrangement
10 comprising:
a range
actuating
gear
10G
having
a plurality of
first
locking
elements 10
a
corresponding to the
plurality of
locking elements 112L of said
medium range
drive
g
ear 112
;
a
plurality of second locking elements 10
b
corresponding to the
plurality of locking elements 102L of said high range coupler 102H
;
a first portion 10
F
extending from corresponding side portion
10x
of
said range actuating
gear 10
G
, the first portion 10
F
de
fining a
plurality of
locking elements
10
c
corresponding to the
plurality of
locking elements
110L of
said
low range driven gear 110;
and
a second portion 10
S
extending from corresponding
another
side
portion
10y
of
said
range
actuating
gear 10
G
, the se
cond portion 10S
defining a portion 10P
extending
from
the second portion 10S
,
and
a shift
fork lug
receiving
portion
10L
between
corresponding another side portion
10y of said range actuating gear 10G
and the
portion 10P
of the
second
portion 10S
,
where
the shift fork lug
receiving
portion
10L
is adapted to
receive
a plurality of lugs 120L of said shift fork 120 therein to
facilitate
engagement of
the
plurality of lugs
120L
of
said
shift fork
120
with
corresponding another side portion
10y
of said range ac
tuating gear 10G and
the
portion 10P of the
second portion 10S
,
wherein
said range
actuating
gear 10G is movably connected to a
range output shaft 106 between
said
high range coupler 102H and
said
low
range driven gear 110;
39
/
51
said range
actuating
gear 10G is adapted to move
from a
neutral
range position
(N1) to a low range position (L)
in a direction towards
said
low range driven gear 110
therein
to enable engagement of the plurality of
locking elements 10
c
of the first portion 10F of said range
ac
tuating
gear
10G with corresponding plurality of locking elements 110L of
said
low
range driven gear 110
thereby facilitating actuation of
said
low range driven
gear 110
in response to the movement of
at least one of said shift fork 120
and
a shifter bush
116
from
the
neutral range position
(N1) to
the
low range
position (L)
;
s
aid range
actuating
gear 10G is adapted to move
from
at least one of
the
neutral range position
(N1)
and
another neutral range position
(N2)
to a
medium range position (M) therein t
o enable engagement of
the
plurality of
first locking elements 10a of said range actuating gear 10G with
corresponding plurality of locking elements 112L of
said
medium range
drive gear 112
thereby facilitating actuation
of said
medium range drive gear
112
in response to
the
movement of
at least one of
said
shift fork 120 and
said
shifter bush 116
from
at least one of
the
neutral range position
(N1)
and
another neutral range position
(N2)
to the medium range position (M)
respectively
;
and
said range actuating
gear 10G is adapted to move
from
another
neutral range position
(N2) to a high range position
(H)
in a direction
towards
said
high range coupler
102H therein to enable engagement of the
plurality of
second
locking elements 10
b
of said
range
actuating
gear 10G
with corresponding plurality of locking elements 102L of
said
high range
coupler 102H thereby facilitating actuation of
said
high range coupler 102H
in response to the movement of
at least one of said shift fork 120 and
said
shift
e
r
bush 116
from the
another neutral range position
(N2) to the high
range position (H)
.
40
/
51
2.
The range actuation arrangement 10 as claimed in claim 1, wherein
the
plurality of
first
locking element
s
10a of said range
actuating
gear 10G is at
least a plurality of
external
teeth (
external
splines)
.
3.
The range actuation arrangement 10 as claimed in claim
2
, wherein the
plurality of
second
locking elements 10b of said range
actuating
gear 10G is
at least a plurality of in
t
ernal t
eeth (internal splines).
4
.
The range actuation arrangement 10 as claimed in claim
3
, wherein
the
plurality of locking elements 10c of the first portion 10F of said range
actuating gear 10G is at least a plurality of in
ternal teeth (internal splines).
5
.
The range actuation arrangement 10 as claimed in claim
4
, wherein the
portion 10P of the second portion 10S of said range actuating gear 10G
is
radially extending along the circumference of the second portion 10S, where
the portion 10P is at
least
a locki
ng collar (stopper) adapted to restrict the
releasing of said shift fork 120 from said range actuating gear 10G.
6
.
The range actuation arra
ngement 10 as claimed in claim 5
, wherein the shift
fork lug receiving portion 10L of the second portion 10S of said range
actuating gear 10G is at a groove (circumferential groove) provided on the
second portion 10S between the side portion 10y of said range actuating gear
10G and the p
ortion 10P of the second portion 10S of said range actuating
gear 10G.
7
.
The range actuation arrangement 10 as claimed in claim 1, wherein
the
plurality of locking elements 102L of
t
he high range coupler 102H of
said
range input shaft
102
is at least
a plurality of external teeth (external
splines),
where said high range coupler 102H
is integrated with said
range
input shaft 102 at a predetermined position.
41
/
51
8
.
The range actuation arran
gement 10 as claimed in claim 1
, wherein the
plurality of locking
elements 112L of said
medium range drive gear 112
is at
least a plurality of externa
l teeth (external splines).
9
.
The range actuation arrangement 10 as claimed in claim 1,
wherein the
plurality of locking elements 110L of said low range driven gear 110
is at
least a plurality of external teeth (external splines)
.
10.
The range actuation arrangement 10 as claimed in claim 1, wherein
said
range actuating gear 10G is adapted to move to at least one of the low range
position (L), the medium range position (M
) and the high range position (H)
thereby facilitating actuation of
at least one of
said
low range driven gear
110, the medium range drive gear 112 and the high range coupler 102H
respectively
in response to the movement of at least one of said shift fork
120 and a shifter bush 116 to
at least one of
the low range position (L)
, the
medium range position (M) and the high range position (H) respectively on
engagement of a range lever 114 adapted to be shifted to at least one of the
low range position (L), the medium range position (M) and the high range
position (H) respectively.
1
1
.
The range actuation arrangement 10 as claimed in claim 1
0
, wherein
the
range lever 114 of
said power transmission unit 100 is configured to be
provided with a sequential gate shift pattern (L
—
N1
—
M
—
N2
—
H, where L
represents low range position, N1 rep
resents neutral range position, M
represents medium range position, N2 represents
another neutral range
position
and H represents high range position).
1
2
.
A power transmission unit 100 for a vehicle, said power transmission unit
100 comprising:
a range
input shaft 102 having a
high range coupler 102H adapted to
be integrated with said range input shaft 102 at a predetermined position,
where
the
high range coupler 102H defines a plurality of locking elements
102L; and
42
/
51
a
constant mesh r
ange
driving gea
r 102C
adapted to be integrated
with said range input shaft 102
at a predetermined position
and provided at a
predetermined distance from the high range coupler 102H
;
a range counter shaft 104 having a low range driving gear
104G
adapted to be integrated
with said range counter shaft 104
at a predetermined
position
and provided at a predetermined distance from corresponding end
of said range counter shaft 104
;
a constant mesh
range
driven gear
108
adapted to be mounted onto
said range countershaft 104
at a predetermined position
and rotatably
connected to
the
constant mesh driving gear 102C
of said range input shaft
102
;
a
low range driven gear 110
adapted to be mounted onto
a
range
output shaft
106 through a
low range driven bush 122
at a predetermin
ed
position and rotatably connected to the low range driving gear
104G of said
range counter shaft 104
, said low range driven gear
110
defines a plurality of
locking elements 110L
;
a
medium range drive gear 112
adapted to be
mounted onto said
range count
er shaft
104
at a predetermined position and
provided at a
predetermined distance from said constant mesh range driven gear 108, said
medium range drive gear 112
defines a plurality of locking elements 112L
;
a shifter bush 116 adapted to be mounted onto
a shifter rod 118 at a
predetermined position;
a shift fork 120 adapted to be connected to said shifter rod 118 at a
predetermined position, said shift fork 120 having a plurality of lugs 120L;
and
a range actuating gear 10G having a plurality of first locking
elements 10a corresponding to the plurality of locking elements 112L of said
medium range
drive
gear 112;
a plurality of second locking elements 10b corresponding to the
plurality of locking
elements 102L of
the
high range coupler 102H
of said
range input shaft 102
;
43
/
51
a first portion 10F extending from corresponding side portion 10x of
said range actuating gear 10G, the first portion 10F defining a plurality of
locking elements 10c correspon
ding to the plurality of locking elements
110L of said low range driven gear 110; and
a second portion 10S extending from corresponding another side
portion 10y of said range actuating gear 10G,
where
the second portion 10S
defining a portion 10P extend
ing from the second portion 10S, and a shift
fork lug engaging portion 10L
between
corresponding another side portion
10y of said range actuating gear 10G and the portion 10P of the second
portion 10S
, where the shift fork lug receiving portion 10L is adap
ted to
receive the
plurality of lugs 120L of said shift fork 120 therein to facilitate
engagement of the plurality of lugs 120L of said shift fork 120 with
corresponding another side portion 10y of said range actuating gear 10G and
the portion 10P of the
second portion 10S
,
wherein
said range actuating gear 10G is movably connected to
said
range output shaft 106 between
the
high range coupler 102H
of said range
input shaft 102
and said low range driven gear 110;
said range actuating gear 10G is adapted
to move from a
neutral
range position
(N1) to a low range position (L) in a direction towards said
low range driven gear 110 therein to enable engagement of the plurality of
locking elements 10c of the first portion 10F of said range actuating gear
10G wi
th corresponding plurality of locking elements 110L of said low
range driven gear 110 thereby facilitating actuation of said low range driven
gear 110 in response to the movement of at least one of said shift fork 120
and
said
shifter bush 116 from the
neu
tral range position
(N1) to the low
range position (L);
said range actuating gear 10G is adapted to move
from at least one of
the
neutral range position
(N1) and
another neutral range position
(N2) to a
medium range position (M) therein to enable engage
ment of the plurality of
first locking elements 10a of said range actuating gear 10G with
corresponding plurality of locking elements 112L of said
medium range
44
/
51
drive gear 112
thereby facilitating actuation
of said
medium range drive gear
112
in response to
movement of at least one of said shift fork 120 and said
shifter bush 116 from at least one of the
neutral range position
(N1) and
another neutral range position
(N2) to the medium range position (M)
respectively; and
said range
actuating
gear 10G is ad
apted to move from the
another
neutral range position
(N2) to a high range position (H) in a direction
towards
the
high range coupler 102H
of said range input shaft 102
therein to
enable engagement of the
plurality of second locking elements 10b of said
ra
nge actuating gear 10G with corresponding plurality of locking elements
102L of
the
high range coupler 102H thereby facilitating actuation of
the
high range coupler 102H in response to the movement of at least one of said
shift fork 120 and said shifter bu
sh 116 from the
another neutral range
position
(N2) to the high range position (H).
1
3
.
The power transmission unit 100 as claimed in claim
1
2, wherein said power
transmission unit 100 further comprising a range lever 114 adapted to be
shifted to at least one of the low range position (L), the medium range
position (M) and the high range position (H) therein to move
said
shifter
bush 116 to at
least one of the low range position (L), the medium range
position (M) and the high range position (H) respectively thereby moving
said
shifter rod 118 along a predefined direction therein to move
said
shift
fork 120 and
said range actuating
gear 10G to at
least one of the low range
position (L), the medium range position (M) and the high range position (H)
respectively
thereby facilitating actuation of at least one of
said
low range
driven gear 110,
said
medium range drive gear 112 and the high range
coupl
er 102H respectively.
14
.
The power transmission unit 100 as claimed in claim 1
2
,
wherein the
plurality of first locking elements 10a of said range actuating gear 10G is at
least a plurality of ex
ternal teeth (external splines)
.
45
/
51
15
.
The power transmiss
ion unit 100 as claimed in claim
14
, wherein the
plurality of second locking elements 10b of said range actuating gear 10G is
at least a plurality of in
ternal teeth (internal splines).
16
.
The power transmission unit 100 as claimed in claim
15
, wherein th
e
plurality of locking elements 10c of the first portion 10F of said range
actuating gear 10G is at least a plurality of in
ternal teeth (internal splines)
.
1
7
.
The power transmission unit 100 as claimed in claim
1
6
, wherein the shift
fork lug receiving
portion 10L of the second portion 10S of said range
actuating gear 10G is at
least
a groove (circumferential groove) provided on
the second portion 10S between the side portion 10y of said range actuating
gear 10G and the portion 10P of the second portion
10S of said range
actuating gear 10G.
1
8
.
The power transmission unit 100 as claimed in claim 1
2
, wherein the
plurality of locking elements 102L of the high range coupler 102H of said
range input shaft 102 is at least a plurality of external teeth (ext
ernal
splines).
19
.
The power transmission unit 100 as claimed in claim 1
2
, wherein the
plurality of locking elements 112L of said
medium range drive gear 112
is at
least a plurality of external teeth (external splines), where said
medium
range drive gear 112
is
adapted to be
mounted onto said range counter shaft
104 at a predetermined position and provided at a predetermined distance
from said constant mesh range driven gear 108 by providing a first spacer
124F between said constant
mesh range driven gear 108 and said medium
range
drive
gear 112.
2
0
.
The power transmission unit 100 as claimed in claim 1
2
, wherein the
plurality of locking elements 110L of said low range driven gear 110 is at
least a plurality of external teeth (exter
nal splines), where said low range
driven gear 110 is adapted to be mounted onto said range output shaft 106
46
/
51
through said
low range driven bush 122
at a predetermined position and
provided at a predetermined distance from a range output shaft bearing
126D
by providing at least one of a second spacer 124S and a third spacer
124T between said low range driven gear 110 and the range output shaft
bearing 12D.
2
1
.
The power transmission
unit 100 as claimed in claim 19, wherein said range
lever 114
is provided with a sequential
gate
shift pattern (L
—
N1
—
M
—
N2
—
H, where L represents low range position, N1 represents neutral range
position, M represents medium range position, N2 represents
another neutral
range position
and H represents high range positio
n).
2
2
. A method 200
for
actuating at least one of a low range driven gear
110
, a
medium range drive gear 112
and a high range coupler
102H
in a power
transmission unit 100
of a vehicle,
said method 200 comprising:
providing said power transmission
unit
100
with a range actuation
arrangement 10 comprising a range
actuating
gear 10G
having a plurality of
first locking elements 10a corresponding to a plurality of locking elements
112L of said medium range
drive
gear 112;
a plurality of second locking ele
ments 10b corresponding to a
plurality of locking elements 102L of said high range coupler 102H;
a first portion 10F extending from corresponding side portion 10x of
said range actuating gear 10G,
where
the first portion 10F defining a
plurality of lock
ing elements 10c corresponding to a plurality of locking
elements 110L of said low range driven gear 110; and
a second portion 10S extending from corresponding another side
portion 10y of said range actuating gear 10G,
where
the second portion 10S
defining a portion 10P extending from the second portion 10S, and a shift
fork lug engaging portion 10L between corresponding another side portion
10y of said range actuating gear 10G and the portion 10P of the second
portion 10S, wh
ere the shift fork lug receiving portion 10L is adapted to
receive
a plurality of lugs 120L of a shift fork 120 therein to facilitate
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/
51
engagement of the plurality of lugs 120L of said shift fork 120 with
corresponding another side portion 10y of said range
actuating gear 10G and
the portion 10P of the second portion 10S
;
moving said range actuating gear 10G from a
neutral range position
(N1) to a low range position (L) in a direction towards said low range driven
gear 110 therein to enable engagement of th
e plurality of locking elements
10c of the first portion 10F of said range actuating gear 10G with
corresponding plurality of locking elements 110L of said low range driven
gear 110 thereby facilitating actuation of said low range driven gear 110 in
respon
se to the movement of at least one of said shift fork 120 and a shifter
bush 116 from the
neutral range position
(N1) to the low range positi
on (L);
moving
said
range actuating gear 10G
from the low range position
(L) to the
neutral range position
(N1) i
n a direction away from said low
range driven gear 110
therein to enable dis
-
engagement of the plurality of
locking elements 10c of the first portion 10F of said range actuating gear
10G with corresponding plurality of locking elements 110L of said low
ran
ge driven gear 110 thereby facilitating de
-
actuation of said low range
driven gear 110 in response to the movement of at least one of said shift fork
120 and
said
shifter bush 116 from the low range position (L) to the
neutral
range position
(N1);
moving
said range actuating gear 10G from the
neutral range
position
(N1) to a medium range position (M) therein to enable engagement
of the plurality of first locking elements 10a of said range actuating gear
10G with corresponding plurality of locking elements
112L of said
medium
range drive gear 112
thereby facilitating actuation
of said
medium range
drive gear 112
in response to movement of at least one of said shift fork 120
and said shifter bush 116 from the
neutral range position
(N1) to the medium
range p
osition (M)
;
moving said range actuating gear 10G from the medium range
position (M) to
another neutral range position
(N2) therein to enable dis
-
engagement of the plurality of first locking elements 10a of said range
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/
51
actuating gear 10G with correspondin
g plurality of locking elements 112L of
said
medium range drive gear 112
thereby facilitating de
-
actuation
of said
medium range drive gear 112
in response to movement of at least one of said
shift fork 120 and said shifter bush 116 from the medium range po
sition (M)
to
another neutral range position
(N2)
;
and
moving said range actuating gear 10G
f
rom
another neutral range
position
(N2) to a high range position (H) in a direction towards said high
range coupler 102H therein to enable engagement of the
plur
ality of second
locking elements 10b of said range actuating gear 10G with corresponding
plurality of locking elements 102L of said high range coupler 102H thereby
facilitating actuation of said high range coupler 102H in response to the
movement of at lea
st one of said shift fork 120 and said shifter bush 116
from
a
nother neutral range position
(N2) to the high range position (H)
.
23.
The method 200 as claimed in claim 22, wherein
moving said range
actuating gear 10G to at least one of the low range position (L), the medium
range position (M) and the high range position
(H)
therein to facilitate
actuation of at least one of said low range driven gear 110, said medium
range drive gea
r 112 and said high range coupler 102H in response to the
movement of said shift fork 120 and said shifter bush 116 to at least one of
the low range position (L), the medium range position (M) and the high
range position (H) respectively on engagement of a
range lever 114 adapted
to be shifted to at least one of the low range position (L), the medium range
position (M) and the high ra
nge position (H) respectively.
2
4
.
The method 200 as claimed in claim
22
,
further comprising
a method step of
moving said r
ange actuating gear 10G from the high range position (H) to
another neutral range position
(N2) in a direction away from said high range
coupler 102H therein to enable dis
-
engagement of the plurality of second
locking elements 10b of said range actuating g
ear 10G with corresponding
plurality of locking elements 102L of said high range coupler 102H thereby
facilitating de
-
actuation of said high range coupler 102H in response to the
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51
movement of at least one of said shift fork 120 and said shifter bush 116
fro
m the high range position (H) to
another neutral range position
(N2) on
engagement of
said
range lever 114 adapted to be shifted from the high
range position (H) to
another neutral range position
(N2).
2
5
.
The method 200 as claimed in claim
2
4
,
further
co
mpris
ing
a method step of
moving said
range actuating gear 10G
from the
another neutral range
position
(N2) to the medium range position (M) therein to enable
engagement of the plurality of first locking elements 10a of said range
actuating gear 10G with c
orresponding plurality of locking elements 112L of
said
medium range drive gear 112
thereby facilitating actuation
of said
medium range drive gear 112
in response to movement of at least one of said
shift fork 120 and said shifter bush 116 from
another neu
tral range position
(N
2
) to the medium range position (M) on engagement of said range lever
114 adapted to be shifted from
another neutral range position
(N
2
) to the
medium range position (M)
.
50
/
51
26
.
The method 200 as claimed in claim
25
,
further comprising a method step of
moving said range actuating gear 10G from the medium range position (M)
to the
neutral range position
(N1) therein to enable
dis
-
engagement of the
plurality of first locking elements 10a of said range actuating gear 10G
with
corresponding plurality of locking elements 112L of said
medium range
drive gear 112
thereby facilitating
de
-
actuation
of said
medium range drive
gear 112
in response to movement of at least one of said shift fork 120 and
said shifter bush 116 from th
e medium range position (M)
to the
neutral
range position
(N1)
on engagement of said range lever 114 adapted to be
shifted from the medium range position (M)
to the
neutral range position
(N1)