THE KREIS GEAR TRANSMISSION

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP83-00415R003900070010-0
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 8
• Document Creation Date: December 14, 2016
• Document Release Date: March 15, 2002
• Sequence Number: 10
• Publication Date: December 9, 1949
• Content Type: REPORT

Approved For Release 2002/08/14: CIA-RDP83-00415R003900070010-0
CLASSIF?ICA 0,11`4
CENTRAL IN T ELLIG
ENCE AGENCY REPORT NO.
INFORMATION REPORT
COUNTRY Germany (Russian Zone)
SUBJECT The Kreis Gear Transmission
25X1 ACE
ACQUIRED
DATE OF INi7-
1A
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CD NO,
DATE DISTR, 9 Dec. 1 49
NO. OF PAGES 3
NO. OF ENCLS. 5*
(LISTED BUM)
PPLEMENT TO
WORT NCO.
The following information has been provided on the Weis''
transmission:
19 The "Kneis^' transmission-named after the designer Fritz Kraj =-
is a gear transmission with full automatics gear shifts except
for the reverse position. Three-speed transmissions for
passenger cars were so far ,:manufactured T ey can be
substituted for the conventional clutch go r unit in most
passenger oars,
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20 No reports have been received on the installation of "Weis"
transmissions in Soviet tanks although this can be done at
any time,
3. The "Kreis" transmission (see Annex 1) is a purely mechanical
cluster gear improved by centrifugal and frecvrheel clutches
Shifting of the three forward speoc1.s is done by a fully-automatic
mechanism and depenCs on the rate of speed The proper ad jus t;; ent
of the mechanism ensures the complete tractivo power of the eng:i.,.o
Gear shifting is Cone smoothly and without loss of gas, ;.ithout
applying brakes, a a oecial reverse idler rear device stop6and
restarts the vehicle for mountain climbing m Driving is done
only by applying the gas pedalo
0 The three centrifugal clutches are intercoms ce t,ed in the clutch
casing (Annex 1, left side). The clutch units are flanged to
the crankshaft of the engine and simultaneously serve
as flywheel. By t?::'o hollow shafts and. one continuous shaft,
the clutches are connected ,with he respective gear ,-;heels a.
and the cerc,an shaft (in direct motion)
sr~ ~
5? The first gear snift (An.ne:c 3 and 4) is.released directly M
from the crankshaft. it is a simple internal shoe-centrjf al
clutch with the individual parts (shoe with clutch lining), cn
serving as fly weights. They are held to~et.her by a reced c
helical spring (garter spring). Vter the idling speed i
passed the fly woights overcome t.it.o force of the helical cap
4
spoing and press against the into ncal side of the casing.
C LASS 117*1C,4 ON S ,CR1 T
irk?iE f M 'sY z ~"
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'he scar shift then slider in very
OLIOOthly. .Ii tli an inercasin numbr of revolutions
the' dear shift secures a ri id connection by its
quadratics"11 ? incroasing ad?2e: ion. iho operated gear
shift transmits its :-lotion to the countershaft by a
hollow shaft and the first train sear wheels, then to
the cardan s.iaf t and on to th. car itself by the
driving; twin scar wheels. In the driving dear wheals
(Annex 29 first sear s.rift) are freewheel catches which
are .in ? ja:imint position when driven by the ensine but
ar released when driven by the cardan shaft. It
indicates that freew,-vheelins of the vehicle is always
connected *,i th the first scar shift. bteppins on the
gas p dal means ? :luteiiin ; in and utartins; releasing
the ;;as pedal t declatchins 'rid freowhceling,
6. The running center gear i le ,'l of the countershaft drives
the -ear wheel of the wain shaft is connected
with the centrifugal clutch of the second. gear shift by
another hollow jhaft. ya J clutch is a sj)ecial design
(Annex 3 and 5) with three h..iieal springs and axially
moving; clutch ;elates. it i.c therefore not driven by the
engine brat by the countershaft with Scared--down revolu-
tions. It is adjusted to ci~c tci: in as soon as the first
gear uliift lies reacted it. to) ,breed. the fly weights
overoo:ae the force of the helical springs and the clutch
cornpreas".On syzrings slide in tad gear shift by means of
thrust b-il.ls. fhe center t'wvvin -ear wheel. is then driven
(.,nnex 29 secon -?e r eilift). :iho treater transmission
results in a quicker motion of the countershaft thus out-
ruririin, the firs' fr:c r11e l and the first gear shift. As
the first freetiz;heel is released, tale first gear shift
rcrosins ready for operation. It sets in as soon as the
sp-od is lowered and the second gear shift is auto:aati--
c:ally releaseG.
7. he third gear ehift (Annex 3 and 5) is at the side of
the rain shaft (direct motion) which is next to the engine .
It lies the Oa:ze design as the second star shift. It is
lire. ctl t driven by the :gain shaft and thus by the cardan
shaft. s oor as the cardan shaft re as ches the required
nv.?aser of :revolutions thin third gear shift clutches in
w.illie the s ;cord freewheel p?7eri its overtaiiirl the second
gear .:haft. (Annex 2, third g ar :j1-lift).
All the : gear shif is are now in operation. The third
e;ar ~lhift is released with decreasing speed, and power
tr onsni osion is t i:cen over autonaatically* by t: e second
and t en till:: first ;e ' Iiifto
'- e011nical design of the e tri fugal clutches of t le
rst and second ,;ear is si ni ~i.cant. Ti; is c:iaract :ris-
tic of -those cl(Attches that t i; declutching iccilanism
oierates at l0>,,er nuaa'::er of 1-evolutions than the alutch-
in :"pin uee ua1e2Ii, i;i is reoai;t.~ts in en ovE'.1'1.:.}i'Jping
positf.on preventing flue cuation of the different -ear
.ping l;) riod c ~n be zz uc: by 0ac1:
tarot tlin, the as pedal. 21 13 centrifugal devices
of the clu'..oncs for the first ge it oil,- ...ft have a radial
:ffe'' '. 1 oot)er ee s++ n' 1 n.t- :'s p r 7 c?cn
iolc.S of t .~ b?~~irl~,~levioes. Mil f._; n,; th calls
au i:. . Yi1 Of tact c3spression u )rings press ageins t the
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3z ii.JTA
walls of the rim on both sides. As soon as the errain."r
devices move, the bore.ioles pass the ed; a of the rim,,
The balls then aro thrust on both aides into the clutch
ring and effect a radial preerure on the counter rind
which is flanged to the engine flywheel. rimo the
clutch of the rear is let in. ,)eclutchin~; is not
possible at the same number of revolutions but only at
a reduced speed because the edge of the rim prevents the
backrun of the. balls. This re:luires an increased centri-
petal force count erictin; the motion of the centrifugal
armin devices. Lie* three helicul s Brings coiled around
the arming devices c?.en only effect this centripetal farce,
if the counter force; i.e. the c:n rifu; al force is furth&r
reduced. 2a, driving speed must be reduced to bring
about this mechanical process.
.y tb.; forward gears are operated automatically there is
only , a' small hand lever on th., instrument board,which
operates the reverse gear and cn also release a freewheel
catch, if the second gear shift is needed for the braking
effect in clown-'hill motion. The er,; ine ce:n also be thrown
into this* gear by dovinhill towin of the vehicle. The
third gear shift slides in directly without preceding
free noel position. It has the ea; a engine brake effect
as in conventional transmissions. Tie hand-lever also has
a neutral ad j ~:hent for ra inin the engine at a hi.; h
number of revolutions without moving the vehicle.
10. Another feature of tie iris transmission is its reverse
'ear ca tch needed for uphill motion. A third freewheel
'Annex ]. and 2, second afar unift) with an opposite
rotary effect survoa this purpose. If the car has the
tendency -to roll back from an uphill stop, the third and
second frwo ii mel are blocked and t_le vehicle is propped
against the Z~Iort intercalated shaft piece. If the
throttle is closed, this freewheel also effects a clamp
confection between the cardsan shaft and the driving
pinion of the second goar, thus preventing the clt tch
within the range of the second gear : haft to be dis-
enga;;ed for o `.herwise the decrease of speed aould result
in a gear wiunge.
11, The :gels transmission has the following characteristics:
Autoiuatic shiftin ; of all forward speeds
of jerkiness in climbin, starts
Auto..l:ttic adjuctiaerit of the transmission to all speeds
and tracticrha1 Le:istance:
.xono_liic it fuel. consu.:.ption
.Li-le of e. e ion.
5 Annexes: a `' ?r~, ,istt
1 ~ lr:.~noiaisc;ion
2. dear :.hilts
3,' dentrifugai Clutches
5. n
sear :,.lift X30.1
near Cziift %~0.3 and 4.
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it l~ ~1 ~ s i
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 Approved For
iak:ra Of t e ~j'Y'~i15w?118S on 1- Chia
1st gear shift
2n1d gear shift
,jrd gear shii t
dear wheels with freev!hDO1
; i left a.d 2 ri ht )
gear ti,~ ee it:.
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Centrifugal clutches
Bngine siCS -Notion of game shift Ns.3
shifts No.2 a 3
" < < shut No.1
C ardsa sides-scotioa of sear shift No