PLANETARY CHANGE-SPEED GEAR UNIT SHIFTABLE UNDER LOAD

CHANGEMENT DE VITESSES A PLANETAIRES AVEC SELECTEUR DE PLAGES SOUS COUPLE

English Abstract

ABSTRACT


Planetary change-speed gear unit shiftable under load

A planetary change-speed gear unit shiftable under load, in
particular for motor vehicles, comprising an automatic gear control
system and several coupled planetary gear sets, together with clutches
and brakes for attaining drive lines of different gear ratios,
in which only two clutches A, B, disposed for example at the drive
shaft, are in the form of clutches capable of actuation under load,
and the drive torque is in principle transmitted selectively by
way of two drive lines. The remaining clutches and brakes can then
be engaged at any time when they are not involved in the torque
transmission. By suitable choice and positioning of the coupled
planetary gear sets, clutches and brakes in relation to the two
clutches, capable of actuation under load, the individual
constructional elements are utilised for a plurality of purposes,
and provide a simple construction with appropriate gear ratios,
and a comparatively large number of gear positions.

Claims

- 13 -
The embodiments of the invention in which an ex-
clusive property or privilege is claimed are defined
as follows:
1. A planetary change-speed gear unit adapted
to shift under load and more particulary for motor
vehicles, having more than two forward speeds, having
a plurality of coupled planetary gear assemblies,
with clutches and clutch brakes, and with two
clutches (A,B) adapted to shift under load, arranged
in parallel with the input shaft and connected
drivably therewith, characterized in that the
clutches (A-A5,B-B5), adapted to shift under load,
are actuated alternately, at least in the forward
speeds, and connect the input-shaft (1,100 - 104) to
the output-shaft (2,200-204) through two separate
power paths, whereby the gear-elements for the
operation may be used repeatedly for the individual
speeds, their connection to and disconnection from
the respective power-paths being effected by shift
elements resulting in improved quality of shifting
(C,D,E,F,G,H,J,K,L).
2. A planetary change-speed gear unit, adapted
to shift under load, according to claim 1,
characterized in that two single planetary gear
assemblies (sun-wheel, ring-gear, planetary-gear
carrier) (I,II), and a two-stage stepped set of
planetary gears (II), with two ring-gears (24,25), in
the one gear train (IIa) of which are located a



- 14 -

sun-wheel and intermediate gears, three clutches
(C,D,E) not adapted to shift under load, and clutch
brakes (G,H) for changing the forward and reverse
speeds, are arranged with the following connections:
a) the clutch (A), adapted to shift
under load, connects the input shaft (1) to an inner
shaft (3) carrying the sun-wheel (11) and planetary
gear set (I);
b) the clutch (B), adapted to shift
under load, connects the input shaft (1) to the ring
gear (33) of the planetary gear set (III), the
sun-wheel (31) of which is secured to the housing;
c) the clutch (E) connects the
planetary gear carrier (32) of the planetary gear set
(III) to the planetary gear carrier (22) of the
stepped set of planetary gears (II) which is
connected to the planetary gear carrier (12) of the
planetary gear set (I) and to the output shaft (2);
d) the clutch (D) connects the
planetary gear carrier (32) to the sun-wheel (21) of
the stepped set of planetary gears (II);
e) the clutch (C) connects the inner
shaft (3) to the sun-wheel (21);
f) the clutch brakes (G,H,J) are
associated with the ring gears (24,25) of the stepped
set of planetary gears (II) and to the ring gear (13)
of the planetary gear set (I) (Fig.1).


- 15 -

3. A planetary change-speed gear unit
according to claim 1, characterized in that a single
set of planetary gears (sun-wheel, ring-gear,
planet-wheel, planetary gear carrier) (I1) and a
three stage stepped set of planetary gears (IV) with
two ring gears (45,46) in a first gear train (IVa)
and a third gear train (IVc) and two sun-wheels
(41,42) in the first gear train (IVa) and the second
gear train (IVb), intermediate gears (44) being
arranged in the first gear train, together with four
clutches (C1,D1,E1,F1) not adapted to shift under
load, and three clutch brakes (G1,H1,J1) for changing
the forward and reverse speeds, are arranged with the
following connections:
a) the clutch (A1), adapted to shift
under load, connects the input shaft (100) to an
inner shaft (300);
b) the clutch (B1), adapted to shift
under load, connects the input shaft (100) to a first
hollow shaft (600) carrying the carrier of planetary
gear set (I1);
c) the clutch (C1) connects the
carrier (121) of planetary gear set (I1) to the
sun-wheel (41) of the first gear train (IVa) of the
stepped set of planetary gears (IV);
d) the clutch (D1), through a second
hollow shaft (500), connects the ring gear (131) of



- 16 -

the planetary gear set (I1) to the sun-wheel (42) of
the second gear train (IVb) of the stepped set of
planetary gears (IV);
e) the clutch (E1) connects the inner
shaft (300) to the second hollow shaft (500);
f) the clutch (F1) connects the inner
shaft (300) to the carrier (43) of the stepped set of
planetary gears (IV) and to the output shaft (200);
g) the clutch brake (G1) is
associated with the sun-wheel (111) of the planetary
gear set (I1), while the clutch brakes (H1,J1) are
associated with the ring gears (45,46) of the stepped
set of planetary gears (IV) (Fig.3).
4. A planetary change-speed gear unit, adapted
to shift under load, according to claim 1,
characterized in that a three stage (V) and a two
stage (VI) stepped set of planetary gears, having a
common planetary gear carrier (53,56), two clutches
(C2,D2) not adapted to shift under load, and five
clutch brakes (L2,K2,J2,H2,G2) for changing the
forward and reverse speeds, are arranged with the
following connections:
a) the clutch (A2), adapted to shift
under load, connects the input shaft (101) to an
inner shaft (301) carrying the ring gear (54) of the
three stage stepped set of planetary gears (V);
b) the clutch (B2), adapted to shift



- 17 -

under load, connects the input shaft (101) to a ring
gear (64) in the first gear train (VIa) of the two
stage stepped set of planetary gears (VI);
c) the clutch (C2) connects the inner
shaft (301) to the output shaft (201);
d) the clutch (D2) connects the
output shaft (201) to the common planetary gear
carrier (53,63);
e) the clutch brake (L2) is associated
with the second ring gear (65), while the clutch
brakes (K2,J2) are associated with the sun-wheels
(61,62) of the two stage stepped set of planetary
gears (VI);
f) the clutch brakes (H2,G2) are
associated with the two sun-wheels (51,52) of the
second and third gear trains of the three stage
stepped set of planetary gears (V) (Fig. 5).
5. A planetary change-speed gear unit
according to claim 1, characterized in that a
three-stage (V) and a two stage (VI1) stepped set of
planetary gears, with a common planetary gear carrier
(53,66) having widened gears (69), and intermediate
gears (67) meshing therewith, in the two stage
stepped set of planetary gears (VI1), and with two
clutches (C2,D2), not adapted to shift under load,
and six clutch brakes (L2,M2,K2,J2,H2,G2) for
changing the forward and reverse speeds, are arranged



- 18 -
with the following connections:
a) the clutch (A2), adapted to shift
under load, connects the input shaft (101) to an
inner shaft (302) carrying the ring-gear (54) of the
three stage stepped set of planetary gears (V);
b) the clutch (B2), adapted to shift
under load, connects the input shaft (101) to a ring
gear (64) in the first gear train of the two stage
stepped set of planetary gears (VI1);
c) the clutch (C2) connects the inner
shaft (302) to the driven shaft (202);
d) the clutch (D2) connects the
output shaft (2.02) to the common planetary gear
carrier (53,56);
e) the clutch brake (L2) is
associated with the second ring gear (65) and the
clutch brake (M2) is associated with the third ring
gear (38), meshing with the intermediate gear (67),
of the stepped set of planetary gears (VI1);
f) the clutch brakes (K2,J2) are
associated with the sun-wheels (61,62) of the two
stage stepped set of planetary gears (VI1);
g) the clutch brakes (H2,G2) are
associated with the sun-wheels (51,52) of the second
and third of the three stage stepped set of planetary
gears (Fig.7).
6. A planetary change-speed gear unit, adapted

- 19 -

to shift under load, according to claim 1,
characterized in that two single planetary gear
assemblies (sun-wheel, ring-gear, planetary gear)
(I3,II3) and a two stage stepped set of planetary
gears (III3) having two ring gears (34,35), in the
first gear train (III3a) are located a sun-wheel (31)
and intermediate gears (33), together with four
clutches (C4,D4,E4,F4), not adapted to shift under
load, and clutch brakes (G4,H4,J4,K4) for changing
the forward and reverse speeds, are arranged with the
following connections.
a) the clutch (A4), adapted to shift
under load, connects the input shaft (103) to an
inner shaft (304) carrying the ring gear (13) of
planetary gear set (I3);
b) the clutch (B4), adapted to shift
under load, connects the input shaft (103) to the
planetary gear carrier (12) of the first planetary
gear set (I3) which is connected to the ring gear
(23) of the second planetary gear set (II3);
c) the clutch (C4) connects the inner
shaft (304) to a further inner shaft (305) carrying
the sun-wheel (31) of the stepped set of planetary
gears (III3);
d) the clutch (D4) connects the
planetary gear carrier (22) of the second planetary
gear set (II3) to the planetary gear carrier (32) of


- 20 -

the stepped set of planetary gears (III3) which is
secured to the output shaft (203);
e) the clutch (E4) connects the
planetary gear carrier (22) of the second planetary
gear set (II3) to the further inner shaft (305);
f) the clutch (F4) connects the
further inner shaft (305) to the output shaft (203);
g) the clutch brakes (G4,H4) are
associated with the sun-wheels(11,21) of the
planetary gears sets (I3,II3),
h) the clutch brakes (J4,K4) are
associated with the ring gears (34,35) of the stepped
set of planetary gears (III3) (Fig.9).
7. A planetary change-speed gear unit, adapted
to shift under load, according to claim 1,
characterized in that two planetary gear sets
(I4,II4), each comprising intermediate gears (13,23),
and a two stage stepped set of planetary gears
(III4), with two ring gears (33,34) and four clutches
(C5,D5,E5,F5), not adapted to shift under load, and
clutch brakes (G5,H5,L5,K5) for changing the forward
and reverse speeds are arranged with the following
connections:
a) the clutch (A5), adapted to shift
under load, connects the input shaft (104) to an
inner shaft (306);
b) the clutch (B5), adapted to shift



- 21 -

under load, connects the input shaft (104) to the
planetary gear carrier (32) of the stepped set of
planetary gears (III4);
c) the clutch (C5) connects the inner
shaft (306) to the sun-wheel (21) of the planetary
gear set (II4) which is secured to the ring gear (34)
of the second gear train (b) of the stepped set of
planetary gears (III4);
d) the clutch (D5) connects the inner
shaft (306) to the sun-wheel (11) of the planetary
gear set (I4) which is connected to the ring gear
(34) of the planetary gear set (II4);
e) the clutch (E5) connects the inner
shaft (306) to the output shaft (204) which is
secured to the ring gear (14) of the planetary gear
set (I4);
f) the clutch (F5) connects the
planetary gear carrier (22) and the ring gear (24) of
the planetary gear set (II4);
g) the clutch brakes (G5,H5) are
associated with the sun-wheel (31) of the stepped set
of planetary gears (III4) and with the ring gear (33)
of the first gear train (a) of this stepped set of
planetary gears;
h) the clutch brakes (J5,K5) are
associated with the planetary gear carriers (22,12)
of the two planetary gear sets (II4,I4) (Fig.11).


- 22 -
8. A planetary change-speed gear unit, adapted
to shift under load, according to claim 1,
characterized in that the two clutches (A-A5, B-B5),
adapted to shift under load, constitute a structural
unit and are arranged side by side in the axial or
radial direction.
9. A planetary change-speed gear unit, adapted
to shift under load, according to claims 4 or 5,
characterized in that, in order to obtain an
overdrive, the input shaft (101) is connected,
through the clutch (B2), adapted to shift under load,
and the hollow shaft (600), to the ring gear (64) of
the first gear train (VIa,VIla) of the two stage
stepped set of planetary gears (VI,VI1), the
sun wheel (61) and the sun-wheel (51) of the central
gear train (Vb) of the three stage planetary gear set
(V) being supported by the clutch brakes (J2,G2), and
the ring gear (54) of the first gear train (Va) of
the three stage planetary gear set (V), and the inner
shaft (301,302) secured thereto, being connected to
the output shaft (201,202) (Figs. 5 and 7).

Description

~a~3~

The invention relates to planetary change-
speed gear units shiftable under load, in particular
for automatic operation in motor vehicles in accord-
ance with the introductory part of claim l. Such
gear units are known in various constructions, e.g.
from Ott, ~hrlinger, Knoed]er, Zdansevicuis German
publication DE-PS 24 ~7 581 dated August 3, 1978, and
have proved satisfactory in particular when only
relatively few gear ratios are required. However,
each additionally required gear is associated with
high constructional cost not only in terms of the
gear unit itself, but in particular in the control
system, because this has to be adapted to the
respective gear graduation in order to a-ttain good
gear shifting, i.e. as non-jerky as possible, under
all travelling condi~ions. Figures 8 and 9 of the
aforesaid specification show a 6 speed gear unit of
this kind, which satisfies practical requiremen-ts
relatively well, and comprises a high speed forward
gear. In spi-te of the advantage of this gear unit in
relation to constructional cost and gear shiftability
compared with gear units of group construction - only
one clutch or brake is engaged or disengaged in
shifting from one gear to another - seven clutches
and brakes are still necessary, and these have to be
matched to each for automatic shifting.
The object of the inven-tion is tilerefore to

33~
--2--
provide a planetary change-speed gear unit, shiftable
under load, in accordance with the prior art but
which is of reduced constructional cost in terms of
the overall gear unlt and the gear control system,
when measured in terms of the gear graduation which
can be attained and utilized in practice.
This object is completely attained by the
novel features described hereinafter. In all the
gear units, the necessary clutches capable of
actuation under load are reduced to two, these being
actuated alternately in the forward gear position,
whereas the remaining clutches and brakes do not have
to be capable of actuation under load. This leads to
considerable simplification, not only in the gear
unit itself but in particular in the gear control
system, because the matching requirement during gear
shifting can be limited to this double~clutch system,
i.e. the two clutches associated with the input
shaft, whereas the preparation for gear shifting in
the remaining clutches and brakes take place in that
respective drive line which is not loaded.
The gear unit according to the invention
has also the advantage that one single planetary gear
set is not shifted at all, but acts as a constant in
the planetary change-speed gear unit, and the other
single planetary gear set has a planet gear carrier
in common with the stepped planetary gear set.


a ~-~
" ` ~L ~.J

~-3-
Although all planetary gear sets have to be
shifted in the case of the double-clutch gear units
according to one preferred embodiment disclosed, this
particular planetary change-speed gear uni-t has only
one single planetary gear set and one three-stage
stepped planetary gear set.
The two stepped planetary gear sets of
further embodiments disclosed, again have a common
planet gear carrier, so leading to relatively low
constructional cost. By means of widened toothing on
the two-stage stepped planetary gear set for engaging
intermediate gear wheels, and a further outer central
gear wheel with a connection to a brake, a seventh
gear position is obtained, thus providing the gear
unit according to a further embodiment with extremely
satisfactory gear ratios~
Although the two clutches capable of
actuation under load can be disposed at -the most
differing positions in the gear uni-t - e.g. one at
the input and one at the output of the gear unit - it
is advantageous if these clutches are disposed at the
input shaft and possibly also combined into a single
unit, as described hereinafter. The two clutches
when in the form of a single unit allow
simplification in the construction of the gear unit
and control system. If -the two clutches capable of
actuation under load are disposed at the input of the


-3a-
gear unit, then lower moments result, thus allowing
more satisfactory sizing of the two clutches.
Kegresse German publication DE-PS 883 691
dated July 20, 1953 indeed describes a change-speed
gear unit comprising two independent clutches, but
these transmit the drive torque alternately from an
input shaft to an output shaft by way of a respective
preliminary shaft.
Embodiments of the invention are described
in further detail hereinafter, with reference to the
drawings in which:
Figure 1 is a gear diagram of a planetary
change-speed gear unit, shiftable under load,
comprising a double-clutch system and two single
planetary gear sets and one stepped planetary gear
set for e.g. six forward gear positions.
Figure 2 is a tabulation of the respective
clutches and brakes which are

!

~ ~ ~ 3 ~ ~3
--4--


en~aged in each gear position and the overall transmission ratîo
attained in each gear position for a gear unit in accordance
with Figure ].


Figure 3 is a gear diagram correspondi~g to Figure 1,
but compri~ing one single planetary gear set and one three-
stage stepped planetary gear set.


Figure 4 is a tabulation correspo~ding to Figure 2, but
for the gear diagram of Figure 3~


Figure 5 and Figure 7 each show 8 gear diagram corresponding eo
Figure 1, but comprising two stepped planetary gear ~ets on one
planet gear carrier for six and seven gear positions respectively.


Figure 6 and Figurc 8 are tabulations corresponding to
Figure 2, but for the respective gear diagramS of Figures 5 and 7.


Figure 9 and Figure 11 are further embodiment.s in accordance
~ith Figure 1.


Figure 10 and Figure 12 are further tabulations corresponding
to Fig~lre 2 and relating to Figures 9 and 11.



All planetary change~speed gear units in accordance with
Figures I, 3, 5, 7, 9 and 11 have in common the face that clutches
A3 B, which are alternately opPrable and capable of actuation under
load at least in the forward gear positions, are disposed at an inpu~
shaft 1~ 100 to 104, and transmi.t the drive torque alternately by way
of a respective drive line to the output shaft 2~ 200 to 204.


3 ~


The clutche~ e.g. C to F, and br~kes G to X9 which ~llow
different gear ratios ~n the ~orward gear positions and als~
allow ~hiftin~ into the reverse gear position9 a~ showm in
Figur~ 4~ 6, 8~ 10 and 12, sre then operated only when
they are not loaded. Thus while one of the drive lines
tran~mit~ the torque~ it i5 possibl2 to operate thP clutches
and brake6 for the next desired gesr 6hift in the ~econd
dri~e line, which i~ unlos~ea. There is thu~ more time for
any required synchroniEatio~ and o~erloading of such a unit
is preventedO ~he requirement for matching the load tran~mission
from one gear ratio to another gear ratio in the most dif~erent

travelli~g state~ by means of the gear unit control system i~ thus
limited to the two cLutches A and B,capable oif actuation under load,thu~

leading tn con~iderable ~impli~ication~ If the two clutches
A and B are for example disposed adjacent to each ~ther at the
input shaf~ this leads to further sdvantages ~or their operability
and al~o for the con~rol ~ystem in relstio~ to any req~ired
synchroni~ation.


In Figure 1~ planetary gesr ~ets nre ~isposed between the
output shaft 2 and the clutche~ A, ~ on the input ~haft 1 i
the following ~equence~


~ single planetary gear 6et I compri~ing an outer central
gear~wheel 13 and the a~50ciated brake I, a planet gear carrier


12 connectcd to the output shaft 21 and an inner central gear wheel 11
having a connection to the clutch A,capable of actuation under loadg
by way of an inner shaft 3~ and being also connected by way of this
fhaft to a clutch C.


~3~


~ two_~tage stepped planetary gear ~et II compri~ing
intermediate wheels 23 in the fir~t wheel trai~ IIa9 Dnd
outer central gear wheel6 24, ~5 with ~ssoclsted brakeæ G,
and comprising a planet gear carrier 22 b~ich i& connected
both to the planet gear carrier 12 of the fir6t 6 ngle planetary
~ear set 1 and also to the clutch E~ ~nd further compri~ing an
inner c~ntral gear wheel Z1 ln the fir&t gear wheel tr~in IIa
which is connected both to the clutch C on the iDner ~h~ft 3
~nd to the clutch D.


A single planetary gear set III with a fixed connection
by way o the inner central gear ~heel 31 to the CaSing 4, srd
8 connection between the outer cent~al gear wheel ~3 and the clutch B
capable of actuation Inder load. The planet gear carrier 32 is
connected to the already-mentioned.clutche5 E and ~ and D~


~ gear unit arranged as shown in Figure 1 and having the
re~pective engaged clutche6 and brakes 26 sho~n in Figure 2
repre~ents ~ particularly sati~factory ~olutio~, because six
forward and one ~everse gear position~ can be attsined by mean~
of only two &ingle planetary gear ~et~ I, III and one two-~tage
~tepped planetary gear &et II with intermediate gear wheel~,
plu~ three respective clutche~ C9 D, E and bra~e~ G, ~
the high~6t gear position being a direct-coupled gear~ snd 3
Yery high ~tep-down r~tio being possible in the fi~t snd
rever~e gesr po~ition~O It is further advantageou& that the
~in~le planetary gear &et III in the vicinity of the i~put ~h~ft
doe~ not have to be &hiftedO


_7



Fro~ the input ~haft ~nward~g the planetar~ change_6peed
gear unit of Figure 3 con~ist~ of a 6ingle planetary gearset I
which is driven by the clutch Bl capable of actuation under load,
way of the planet gear carrier 1~19 the planet gear c~rrier
also being connccted to a clutch Cl~ The i.nner central gear
wheel 111 is connected to a brake Gl, and the outer central
~ear wheel 131 compri~es a connection to an inner hollow 6haft
503~ on which the clutches Dl and ~ are dispo~edO The
radially inner shaft 300 coming from the clutch ~ is likewi6e
cornected to the clutch El~ and al~o carries the clutch Flo
Th~ three-stage stepped planetsr~ gear 6e-t IV between the output
shaft 200 and the first single planetary gear ~et also ha~
ir~termediate gear wheel~ 44 in the first ge~r wheel train 4a,
and the two onter gear wheel trains IVa and IVc have outer
central gear wheels 45~ 46 with associated brake~ ~ and Il.
~he planet gear carrier 43 is connected to the output shaft 200,
an~ thiR latter is al60 co~nected to a clutch ~1- The inner
central gear wheel of the first gear wheel train IV~ is
connected to the clutch Cl, and the inner central gear wheel
~2 of the ~iddle gear wheel tra~n IVb ha~ D COnDe~tion to the
clutch Dl~ .


Starting from the iDpUt shaft 9 the planetary change-~peed
gear unit of Figure 5 con~i~t6 of ~ three-stage 6tepped planetary
gear ~et ~ and a two-~tage stepped planetar~ gear ~et VI with
a ro~mon planet gear carri.er 53/63, which i~ connected by way
of the clutch D2 to the output Lhaft 2010 The three-6tage
~tepped planetary gear set al.~o ha5 a connection by way of the



outer central ~ear ~heel 54 in the fir6t gear wheel trai~
V~ to an in~er 6h~ft 301~ which i6 al~o oDnnected to the clutch A~
cap~ble o~ actuation under load and the clutch C2. The clutch C~
is Dt the aa~e time ~lso di6posed on the OlltpUt ~haft 201q
The inner central ge~r wheel6 517 5~ of the middle gear wheel
train Vb and ol the fuxther geDr wheel train 5c ha~e ~
respective connection b~ way of the inner 6haft~ 601 and 701
to the clutche~ G2 a~ E2- The ~n~er cen-tral gear wheels of
the two-stage planeta~y gear set 61 and 62 ~re also connected
to the brake6 I2 and ~2 by way of the inner shaft~ 801 and
901~ The DUter central ~ear wheel 64 of the first gear wheel
train VIa is co~nected to the clutch B2capable of actuation under
load 9 a~ the outer central gear wheel 65 of the ~econd gear
wheel train VIb is connected to the br~ke ~2.


~ igure 7 differ~ from Figure 5 only in that the toothing
69 of the ~ear wheel tr~in VIlb ~f the tw0-6ta~e 6tepped
planetary gear 6et is widened, 50 that intermedi~te gear whe~l6
67 with a central gear wheel ~8 and a brake M2 can also be
di~p~sed i~ additisn to the outer central gear wheel 65 with
the brake ~2~


Starting from the input ~haft, the planetary change-6peed
gear unit of ~igure 9 con6i6t6 o~ two 6inele planetary gear
~et~ I3 srd II3, and one tw0~6tage 6tepped plsnetary gear ~et
II ~ with inter~ediate gear wheels 33 in the first 6ear wheel
train III3s. The inner centrsl gear ~heel 11 of the fir6t
~ingle planetary gear set I3 ha6 a connection to the hr3ke G


3 ~


and the outer central gear wheel 13 i~ connected to the inr,~r
aha~t 304, whic~ at the ~a~e time i6 connected to the clutch A~
capable v~ actuation under load, and the clutch C40...A Eurther drive.is poss-
ible by w2y of the clutch B~ capable o~ actuation under load~tv the planet
carrier 12, which is also cohnected to the outer cent~l gear
wheel 23 of the ~econd single planetary gear ~et II3, The
inner central gear wheel of the ~econd singl.e planetary gear
~et has a connection to the brake ~9 and the carrier 22 i~
connected by way of the clutch D4 to the planet gear carrier
of the two-stage 6tepped planetary gear ~et III3~ which
comprises intermediate gear wheel6 33 i~ the first gear wheel
train III~a. In addition9 the planet gear carrier 22 of the
second single planetary gear cet XI3 i6 connected by w~y of
the clutch E4 to the inner 6haft 3057 ~hic~ also ha~ ~ connection
to the i~ner central gear wheel 31 vf the fir~t gear wheel trai~
o~ the *wo-6tage ~tepped plsnetary gear ~et. Th~ in~er ~haft
305 al~D carrie~ the clutch ~4~ which is like~i~e di~po~ed at
the output ~haft 203. The planet gear carrier 3Z ol the two
~tage 6tepped planetary gear ~et III~ also ha~ a connection to
the outp~t shaft 203. Thi~ stepped planetary Kear ~et alsD
compri~es two ~uter central gear wheel~ 349 35 with a~sociated
bra~e~ 4 nd ~44


Starting frDm the ~utput shaft 2049 the pl~netary change-
~peed gea~ ~nit of Figure 11 co~pri~e~ tw~ planetary gcar sets
I4 and IIl~ with intermediate gear wheel6 13 and 237 and a ~tepped
planetary gear ~et III4 co~pri~in~ tWD gear wheel trai~6, the
lnner central gear wheel Df the secDnd gear wheel train lIIl~b
being connected to the brake G5 and th~ outer central gear wheel


~1~33~

--10--
33 of the first gear wheel train III4a being connected to
the brake H5~ The planet gear carr;er 32 of the stepped
planetsry gear set III4 i9 ronnected to the clutch B5, capable
of actuation under load, and the outer central gear wheel 34 i3
connected to the inner ceDtral gear wheel of the second planetary
gear set 2] and to the.clutch C5. The clutch C5 is also connected
by way of the inner shaft 306 ~o the clutch A5 capable of actuation
under load, and t~ the clutches D5 and E$, the clutch E5 being
connected to the output shaft 204 9 which is also connected to the
outer central gear wheel 14 of the first planetary gear set. The
clutch D5 is also connected to the inner central gear wheel 11 of
the first planetary gear set I4 and to the outer central gear wheel
24 of the second planetary gear set II4 and to the clutch F5, wXich
can also provide a connection to the planet gear carrier 22. The
planet gear carrier 22 also carries a brake I5, and the planet gear
carrier 12 of the first planetary gear set I4 is connected to a
brake K5.

The representations of Figures 29 4 3 6~ 8, ~0 and 12 generally
require no further description, because they make it clear which
of tbe clutches A and B capable of actuation under load are engaged
in ~he respecti~e gear positions, and also which clutches C to F
are engaged. It is also apparent which preparatory shiftîng operations
have to be carried out in the respective unloaded driYe line for
shifting into high and reverse speeds. It ;s also apparent that
in the forward gear positions the clutches A and B capable of actuation
under load are engaged alternately, and in addition the gear


~a~


ratio~ i~ all gear positions can be ~een from the figuresO


Particul~rly Eatisfacto~y embDdiment~ are attained b~
Fi~ure6 5 and 7 i~ co~nection with the respecti~e high 6peed
gea.r positions - gear 6 ~f Figure 6 and gear 7 of Figure 8
Although in both embodi~ents the torque i~ tran~mitted from the inpu~
shaft 101, by way o~ the two clutches B2 capable of act~ation
under load and the hollow shaft 600, to the outer central gear wheel

64 in the fir~t gear wheel train ~I~ of the tw0-6tage ~tepped
planetary gear ~et VI~ the output is not taken from the planet
gear carrier as in the ~ormal manner1 but from the outer central
~ear wheel 54 in the fir~t ge~r wheel train ~f the three_stage
planet~ry gear set Vq and from there by way of the radislly
inward lying inner shaft 301 or 302~ which are also connected

to the clutch A2, c2pable of actuation under-load, to ~he output
shaft ~0l or 292.


The two-~tage ~tepped plsnetary gear ~et i~ then ,held
by a brake 52 by way of the ~r~ner central gear wheel 61 of the
fir~t gear wheel train VIa 9 wherea~ the three-stage ~tepped
planetDry gear set Y i6 held by the brake G2 by way of
the inner central gear wheel 51 of the middle g ar wheel trsin

~o .

~ hi~ gear ~peed is also atta-ned without any additional
con~tructional c06t, because the neces6ary clutcnes etc, are

already required for attaining the other gear ~p~eds.


The irvention i~ not l~mitea to the illu~trated change-~peed

~23~

gear un;ts9 but it i~ also for exc~mple possible to additionally
fit these gear units with a torque converter, or again the clutches
A, B capable ~f actuati~n under load can be disposed separated
at various positions in the gear unit.