AUTOMOTIVE
`HANDBOOK
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`TOYOTA Ex. 1014, page 1
`Toyota v. Hagenbuch
`|PR2013-00483
`
`TOYOTA Ex. 1014, page 1
`Toyota v. Hagenbuch
`IPR2013-00483
`
`

`

`
`
`Reproduction, duplication and transla—
`tion
`of
`this publication,
`including
`excerpts therefrom, is only- to ensue
`with our previous written consent and
`with particulars of source. Illustrations.
`descriptions, schematic'diagrams and
`other data serve only for explanatory
`purposes and for presentation of the
`text. They cannot be used as the basis
`for design,
`installation and scope of
`delivery. We undertake no liability for
`conformity of the contents with national
`or local regulations.
`,
`We reserve the right to make changes.
`
`The brand names given in the contents
`serve only as examples and do net
`represent the classification or prefer—
`ence for a particular manufacturer.
`Trade marks are not identified as such.
`
`The following companies provided illus—
`trations and informative material:
`
`-
`Audi AG, lngolstadt;
`Bayerische Motorenwerke AG, Munich;
`Daimler-Benz AG, Stuttgart;
`J. Eberspacher, Esslingen;
`Fichtel u. Sachs AG. Schweinfurt;
`Kienzle Apparatus GmbH, VS-Villingen;
`Sekurit—Glas Union GmbH, Aachen;
`Voith GmbH, Heidenheim;
`.
`Zahnradfabrik Friedrichshafen AG, .
`Friedrichshafen.
`
`
`GmbH, 1986
`
`D—7000 Stuttgart 1.
`QB
`uipment ProduCt Group,
`Wash 50,
`E
`.
`.
`
`emotive fgr Technical Information
`
`Edflcr—in—Chiet:
`
`Dim—Eng. (FH) U. Adler
`
`Editors;
`
`Dipl‘.—lng (FH) H. Bauer,
`i.—ln
`.W. Bazien,
`glazinkir, Marion Herwerth
`
`Production management:
`(3 Berger
`
`it out:
`Dtglxlng. (FH) U. Adler
`
`
`G. Berger
`
`
`Translation:
`
`Editor—in—Chief:
`P. Giriing
`Editor:
`
`J.-F. Salas
`
`
`.
`..
`Translated by:
`lngenieurbiiro fur Technlsche und
`
`Naturwissenschaftliche Ubersetzungen
`Dr. W.-D. Haehl GmbH. Stuttgart,
`
`Edward L, Crosby Ill
`Technical graphics:
`
`Bauer & Partner GmbH, Stuttgart
`
`Joint production:
`
`Jaeger Druck GmbH, Speyer
`The worldwide selling rights and the
`
`right to issue foreign—language licenses
`
`for the original German Edition (19th
`
`Edition, 1985) are held by:
`VDl-Verlag, GmbH
`
`Verlag des Vereins Deutscher
`
`Ingenieure. Graf—Recke—Str. 85,
`
`D—4000 Ddsseldorf 1,
`
`lSBN 3—187418006—9
`
`Printed in the
`Federal Republic of Germany,
`Imprime en République Fédérale
`d’Allemagne.
`
`Editorial closing; 30.9.1986
`
`
`
`Approved Editions under license:
`SAE Society of
`
`Automotive Engineers Inc.
`
`ISBN 0—89 283-518-6
`
`Delta Press Limited
`
`lSBN 1 85 226 00 9
`
`
`
`
`TOYOTA Ex. 1014, page 2
`Toyota v. Hagenbuch
`lPR2013-00483
`
`TOYOTA Ex. 1014, page 2
`Toyota v. Hagenbuch
`IPR2013-00483
`
`

`

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`Braking Equipment (Passenger Cars)
`
`526
`
`Vacuum booster
`The vacuum booster is a pedal—force
`booster which is combined with a tan-
`dem master cylinder. The boost factor 1'
`(see characteristics) can be varied in
`design by an appropriate choice of
`lever control. Via the lever control, a
`proportional assisting force is superim-
`posed on the pedal force, and both act
`together on the tandem master cylin—
`der. At the same time, a reactive force
`is
`conveyed to the
`driver, which
`enables
`him to meter
`the braking
`action correctly. The operating prin-
`ciple is explained in the diagram below.
`Should the booster fail, there remains
`only the pedal force.
`
`Tandem master cylinder
`The tandem master cylinder is operated
`either directly via a pedal ratio or, it the
`pedal force is not sufficient, via a pedal-
`force booster (eg. vacuum booster).
`Operating principle: after passing over
`snifter hole I, the push-rod piston for—
`ces the brake fluid into brake circuit I.
`The compression of the spring and the
`pressure buildup in brake circuit | actuv
`ates the intermediate piston, which
`passes over snifter hole ii and builds up
`pressure in brake circuit II. The brake
`
`to the pedal
`
`pressure is proportional
`force.
`.
`l, which
`The port for brake circuit
`supplies the rear drum brakes, has a
`prepressure valve which assures
`a
`residual pressure of approx. 1.5 bar
`when the brakes are released, This pre-
`vents the entry of air
`through the
`wheel-cylinder seals. The brake circuits
`for disk brakes do not have any pre-
`pressure. With the brakes released, the
`two snifter holes guarantee that there
`can
`be
`temperature-
`and
`leakage-
`related changes in quantity and press-
`ure between the fluid reservoir and the
`brake circuits.
`
`Operating principle in case of failure of
`a brake circuit:
`— Failure of brake circuit I
`The push-rod piston moves forward as
`far as
`the intermediate piston and
`mechanically transmits the force to the
`intact brake circuit
`II, which can thus
`produce the full brake pressure.
`— Failure of brake circuit ll
`The intact brake circuit
`l hydraulically
`pushes the intermediate piston against
`the stop in the housing. It is then poss—
`ible for the full brake pressure to be
`produced in brake circuit l.
`
`
`Vacuum brake booster with lever control
`Characteristics of vacuum brake booster
`as a function of active diameter.
`1 Output force (to tandem master cylinder),
`2 Vacuum connection, 3 Input force (pedal
`(type = active diameter in inches) at
`force), 4 Atmosphere, 5 Working pressure.
`vacuum (0.8 bar),
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`8000
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`600
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`< h
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`4000
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`yllllllfl””lllllll/3.Wt.I
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`I!
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`E
`8
`2on
`E
`Fu 7,
`17:
`a)
`“
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`
`
`3000 N
`
`a)
`3
`p
`5'
`9:
`3
`O 1'1
`”147'
`y ‘ w/thout
`vacuum
`
`
`0 ‘11000
`2000
`Input force FE
`F0
`= Pedal force x pedal ratio
`FA
`Boost factor i = tan a =
`FE — FD
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`TOYOTA Ex. 1014, page 3
`Toyota v. Hagenbuch
`lPR2013-00483
`
`TOYOTA Ex. 1014, page 3
`Toyota v. Hagenbuch
`IPR2013-00483
`
`

`

`
`
`Braking Equipment (Passenger Cars) 527
`
`
`Tandem master cylinder.
`1 Two-chamber fluid reservoir, 2 Housing,
`3 Snifter hole for brake circuit /l,
`4 Compression spring. 5 Sni/ter hole for
`brake circuit I, 6 Push—rod piston, 7 Front
`brake circuit ii, 8 in termediate piston,
`
`The failure of a brake circuit causes a
`considerable reduction in the braking
`effect, a clearly noticeable increase in
`the pedal travel and the loss of brake
`fluid from one of the two chambers of
`the fluid reservoir.
`
`9 Pre-pressure valve, 10 Ftear brake circuit i
`
`
`
`
`Characteristics at a load-sensitive brake-
`pressure—regulating valve.
`
`
`
`
`Brake pressure regulating valve
`The more heavily the driver brakes, the
`greater
`is
`the dynamic
`shifting of
`weight from the rear axle to the front
`axle. With the vehicle empty, the brak-
`ing force at the rear axle may be so
`great that the rear axle locks before the
`front axle. This can lead to instability
`when braking,
`i.e. to skidding. Braking
`stability is obtained when, irrespective
`of vehicle loading, the front axle always
`looks before the rear axle (see charac-
`teristics opposite and legal
`require-
`ments p. 508). The correct braking-
`force distribution can be achieved by
`brake—pressure-regulating valves which
`are installed in the brake lines to the
`wheels of the rear axle. Matched to the
`respective vehicle data, there are vari-
`ous kinds of brake—pressure—regulating
`valves:
`- Brake-pressure-regulating valve with
`fixed changeover pressure,
`— Load—sensitive brake-pressure—regu-
`lating valve with variable changeover
`pressure dependent on vehicle loading.
`The load-sensitive brake-pressure-
`regulating valve
`is mounted in
`the
`region of the rear axle. The compres-
`sion of the suspension between axle
`and body is used as a measure of the
`vehicle loading and is transmitted via a
`mechanical
`linkage
`to
`the
`control
`spring in the brake-pressure—regulating
`valve. The control spring acts on a
`stepped piston. During initial braking,
`the control spring keeps the valve seat
`at
`the stepped piston open until
`the
`brake pressure has reached a
`level
`which, according to the active area of
`the stepped piston, corresponds to the
`force of the control spring. The further
`increase
`in
`pressure
`beyond
`the
`changeover point takes place along a
`slope corresponding to the difference
`in the active diameter of the stepped
`piston.
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`Rear—axlebrakepressure
`
`Front-axle brake pressure J
`
`Load-sensitive brake pressure regulating
`
`
`valve.
`1 From tandem master cylinder,
`2 To wheel brakes, 3 Mechanical linkage,
`4 Control springs, 5 Stepped piston.
`2
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`
`
`Unladen
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`TOYOTA Ex. 1014, page 4
`Toyota v. Hagenbuch
`|PR2013-00483
`
`TOYOTA Ex. 1014, page 4
`Toyota v. Hagenbuch
`IPR2013-00483
`
`