tcvn6821 2001.pdf phanh Ôtô

t I u c h u n v I t n a m

TCVN 6821 : 2001 ISO 611 : 1994

phng tin giao thng ng b -phanh t v moc - t vng

Road vehicles - Braking of automotive vehicles

and their trailers Vocabulary

H ni - 2001

tcvn

Li ni u

TCVN 6821 : 2001 hon ton tng ng vi ISO 611 : 1994 (E/F/R).

TCVN 6821 : 2001 do Ban k thut tiu chun TCVN/TC 22 Phng tin giao

thng ng b v Cc ng kim Vit nam bin son, Tng cc Tiu chun o

lng Cht lng ngh, B Khoa hc, Cng ngh v Mi trng ban hnh.

3t i u c h u n v i t n a m TCVN 6821 : 2001

Phng tin giao thng ng b -Phanh t v moc - T vng

Road vehicles - Braking of automotive vehicles

and their trailers - Vocabulary

1 Phm vi p dng

Tiu chun ny nh ngha nhng thut ng c bn v phanh v thit b phanh. Nhng thut ng ny

ch r cc h thng hoc b phn lin quan n hot ng ca phanh hoc nhng gi tr c trng cho

ton b hoc mt phn s hot ng .

Nhng thut ng c nh ngha trong tiu chun ny p dng cho t, xe c ko v on xe nh

c nh ngha trong TCVN 6211 : 1999 (ISO 3833).

2 Tiu chun trch dn

TCVN 6211 : 1999 (ISO 3833 : 1977) Phng tin giao thng ng b - Kiu - Thut ng v nh

ngha (Road vehicles Types Terms and definitions).

3 Thit b v cc h thng phanh

3.1 Thit b phanh (braking equipment): Tt c cc h thng phanh c lp trn xe gim vn tc

hoc dng xe li hoc gi xe ng yn.

3.2 H thng phanh chnh (service braking system): Tt c cc b phn m tc ng ca chng c

th iu khin c, cho php ngi li trc tip hoc gin tip gim vn tc ca xe trong khi li bnh

thng hoc dng xe li.

TCVN 6821 : 2001

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3.3 H thng phanh d phng (secondary braking system): Tt c cc b phn m tc ng ca

chng c th iu khin c, cho php ngi li trc tip hoc gin tip gim vn tc ca xe hoc

dng xe li trong trng hp h hng h thng phanh chnh.

3.4 H thng phanh dng (parking braking system): Tt c cc b phn cho php gi xe ng yn

bng c cu c kh, ngay c trn b mt nghing v c bit khi khng c ngi li.

3.5 H thng phanh chm dn b tr (additional retarding braking system): Tt c cc b phn

cho php ngi li, trc tip hoc gin tip, n nh hoc gim vn tc ca xe, c bit trn dc di.

3.6 H thng phanh t ng (automatic braking system): Tt c cc b phn phanh xe mt cch

t ng.

V d: Trong trng hp ca xe c ko, h thng phanh t ng c kch hot do s tch ri khi

xe ko mt cch ngu nhin hay c .

4 Cc b phn cu thnh

Mt h thng phanh bao gm b phn cung cp nng lng, b phn iu khin, b phn truyn ng,

c cu phanh v nu cn mt b phn b tr t trn xe ko dng cho xe c ko.

4.1 B phn cung cp nng lng (energy-supplying device): Cc phn ca h thng phanh cung

cp, iu tit v nu cn chuyn ha nng lng cn thit phanh. B phn ny kt thc ni b

phn truyn ng bt u, ngha l ni cc dng khc nhau ca cc h thng phanh (xem 5.2), gm

c dng ca cc ph kin nu c lp, c ngn cch vi b phn cung cp nng lng hoc ngn

cch vi nhau.

Ch thch 1 - iu ny cng p dng cho xe c ko.

4.2 Ngun nng lng (energy source): Phn ca b phn cung cp nng lng, to ra nng lng.

Ch thch 2 - Ngun nng lng c th c t cch ri khi xe (v d i vi h thng phanh kh nn dng

cho moc) v cng c th l sc mnh c bp ca con ngi.

4.3 B phn iu khin (control device): Cc phn ca h thng phanh, khi ngun cho s hot

ng v iu khin tc dng ca h thng phanh ny.

B phn iu khin bt u:

- ti v tr tc dng khi ngi li (hoc mt ngi khc) trc tip tc ng;

- ti v tr tn hiu iu khin c truyn vo h thng phanh khi ngi li gin tip tc ng hoc

khi khng c s tc ng ca ngi li.

TCVN 6821 : 2001

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B phn iu khin kt thc ti ni phn chia nng lng cn thit to ra lc tc dng hoc ni phn

chia mt phn nng lng iu khin lc tc dng .

Ch thch 3 - Tn hiu iu khin c th c truyn trong phm vi b phn iu khin v d bng c kh, kh

nn, thy lc, hoc in, k c dng nng lng ph hoc nng lng khng phi nng lng c bp.

Ch thch 4 - B phn iu khin c th hot ng do:

- tc ng trc tip ca mt ngi, bng chn hoc tay;

- tc ng gin tip ca ngi li hoc khng cn tc ng no (ch trong trng hp xe c ko);

- s thay i p sut trong ng ng ni hoc dng in trong dy cp gia xe ko v xe c ko ti

thi im hot ng ca mt trong cc h thng phanh ca xe ko, hoc trong trng hp h hng.

- qun tnh hoc trng lng ca xe hoc ca mt b phn cu thnh xe (nh s st li hoc tch ri ca

xe ko v xe c ko hoc s h thp ca mt b phn cu thnh).

4.4 B phn truyn ng (transmission device): Cc phn ca h thng phanh, truyn nng lng

c phn chia bi b phn iu khin.

B phn truyn ng bt u ti ni kt thc b phn iu khin hoc b phn cung cp nng lng v

kt thc ti ni bt u c cu phanh.

Ch thch 5 - B phn truyn ng c th l, v d dng c kh, thy lc, kh nn (p sut trn hoc di p

sut kh quyn), in hoc kt hp (nh thy c, thy kh).

4.5 C cu phanh (brake): Nhng phn ca h thng phanh xut hin cc lc chng li chuyn

ng hoc xu hng chuyn ng ca xe.

4.5.1 C cu phanh ma st (friction brake): C cu phanh trong cc thnh phn gn vi phn c

nh ca xe b tc dng t vo mt hay nhiu thnh phn c gn hoc khp vo bnh xe hoc cm

bnh xe bng lc tc dng.

Ch thch 6 - Loi c cu phanh ma st trong hiu qu ca (cc) lc tc dng tng ln do cc lc ma st

c gi l dng t cng ho.

4.5.1.1 C cu phanh tang trng (drum brake): C cu phanh ma st trong cc lc ma st c

to ra gia cc thnh phn c gn vo phn c nh ca xe v b mt bn ngoi hoc bn trong ca

tang trng.

4.5.1.2 C cu phanh a (disc brake): C cu phanh ma st trong lc ma st c to ra gia

cc thnh phn gn vi phn c nh c nh ca xe v b mt ca mt hay nhiu a phanh.

4.5.2 C cu phanh gi khp cng bc (kho) [positive engagement brake (lock)]: C cu

phanh trong cc b phn khng quay ca xe cn ch chuyn ng ca cc thnh phn c gn c

nh vo bnh xe hoc cm bnh xe bng cch gi khp cng bc.

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Ch thch 7 - C cu phanh gi khp cng bc thng ch dng khi xe ng yn.

4.5.3 B hm chm dn (retarder): C cu c chc nng gim hoc n nh tc ca xe, v d nh

trn dc di, nhng khng dng xe li.

4.5.3.1 B hm chm dn bng ng c chy n (retarder by combustion engine): B hm chm

dn thc hin tc ng chm dn ln xe ang chuyn ng khi ng c chy n c ni vi bnh xe

ch ng. Tc dng hm chm dn c to ra bng cc cch v d nh gim lng nhin liu cumg

cp, thu nh ng khng kh cp vo, thu nh ng thot ca kh x hoc bng cch thay i thi

gian m van (su-pp).

4.5.3.2 B hm chm dn bng ng c in (retarder by electric traction motor): B hm chm

dn thc hin tc dng chm dn ln xe ang chuyn ng khi ng c in c ni vi cc bnh xe

ch ng. V d, tc dng hm chm dn trn xe ang chuyn ng c to ra bng cch cho chy

ng c In ch my pht.

4.5.3.3 B hm chm dn thy ng lc (hydrodynamic retarder): C cu trong tc dng hm

chm dn t c do tc ng ca cht lng ln cc thnh phn c lin kt vi mt hoc nhiu

bnh xe hoc vi cc b phn ca h thng truyn lc ca xe c lin kt vi cc bnh xe.

4.5.3.4 B hm chm dn kh ng (aerodynamic retarder): C cu trong tc dng hm chm

dn t c bng cch tng sc cn khng kh (chng hn nh vic s dng cc b mt chuyn

ng).

4.5.3.5 B hm chm dn in t (electromagnetic retarder): C cu trong tc dng hm chm

dn t c do tc ng ca t trng ln a kim loi ang quay c lin kt vi mt hoc nhiu

bnh xe (dng in xoy, hin tng tr) hoc vi cc b phn ca h thng truyn lc ca xe c

lin kt vi cc bnh xe.

4.5.3.6 B hm chm dn ma st (friction retarder): C cu trong tc dng hm chm dn t

c do ma st kh hoc t gia cc thnh phn c gn vo phn c nh ca xe v cc thnh

phn c lin kt vi cc bnh xe hoc vi cc b phn ca h thng truyn lc ca xe c lin

kt vi cc bnh xe.

4.6 B phn b tr trn xe ko dng cho xe c ko (supplementary device on towing vehicle

for towed vehicle): Cc phn ca h thng phanh trn xe ko c dng cung cp nng lng v

iu khin h thng phanh trn xe c ko. B phn b tr gm cc thnh phn nm gia b phn

cung cp nng lng ca xe ko v ng cung cp (bao gm c u ni) v gia (cc) b phn truyn

ng ca xe ko v ng iu khin (bao gm c u ni).

TCVN 6821 : 2001

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5 nh ngha h thng phanh theo c tnh ca cc b phn cu thnh

5.1 nh ngha h thng phanh theo b phn cung cp nng lng (theo ngha ca 4.1)

5.1.1 H thng phanh nng lng c bp (muscular energy braking system): H thng phanh

trong nng lng cn thit to ra lc phanh c cung cp ch do sc lc t nhin ca ngi li.

5.1.2 H thng phanh c tr lc (energy / power-assisted): H thng phanh trong nng lng

cn thit to ra lc phanh c cung cp bi sc lc t nhin ca ngi li v mt hoc nhiu b

phn cung cp nng lng.

V d:

- H thng phanh tr lc chn khng (vi bu chn khng).

- H thng phanh tr lc kh nn (vi bu khng kh).

- H thng phanh tr lc thy lc (vi bu thy lc).

5.1.3 H thng phanh khng c nng lng c bp / tr lc hon ton (non-muscular energy /

full-power braking system): H thng phanh trong nng lng cn thit to ra lc phanh c

cung cp bi mt hoc nhiu b phn cung cp nng lng ngoi tr sc lc t nhin ca ngi li.

V d:

- H thng phanh hi hon ton

- H thng phanh thy lc hon ton

- H thng phanh thy lc iu khin bng kh nn

Ch thch 8 - Tuy nhin, loi tr trong nh ngha trn h thng phanh trong ngi li c th tng lc phanh

bng tc ng c bp ln h thng ny trong trng hp mt nng lng hon ton.

5.1.4 H thng phanh qun tnh (inertia braking system): H thng phanh trong nng lng cn

thit to ra lc phanh pht sinh t vic moc dch chuyn st li xe ko.

5.1.5 H thng phanh trng lc (gravity braking system): h thng phanh trong nng lng cn

phanh c cung cp bi s h thp mt b phn cu thnh ca moc do trng lc.

5.1.6 H thng phanh l xo (spring braking system): H thng phanh trong nng lng cn

phanh c cung cp bi mt hay nhiu l xo c tc dng nh mt vt tch nng.

5.2 nh ngha h thng phanh theo cch b tr b phn truyn ng

5.2.1 H thng phanh dng n (single-circuit braking system): H thng phanh c b phn

truyn ng gm mt dng n.

Ch thch 9 - Trong trng hp c h hng trong b phn truyn ng, b phn ny khng th truyn c

nng lng dng to ra lc tc dng.

TCVN 6821 : 2001

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5.2.2 H thng phanh dng kp (dual-circuit braking system): H thng phanh c b phn truyn

ng gm hai dng.

Ch thch 10 - Trong trng hp c h hng trong b phn truyn ng, b phn ny vn c th truyn ton

b hoc mt phn nng lng dng to ra lc phanh.

5.2.3 H thng phanh nhiu dng (multi-circuit braking system): H thng phanh c b phn

truyn ng gm mt vi dng.

Ch thch 11 - Trong trng hp c h hng trong b phn truyn ng, b phn ny vn c th truyn ton

b hoc mt phn nng lng dng to ra lc phanh.

5.3 nh ngha h thng phanh theo on xe

5.3.1 H thng phanh ng n (single-line braking system): T hp trong h thng phanh

ca cc xe ring bit tc dng theo cch mt ng n c dng cho c vic cung cp nng lng

v iu khin h thng phanh ca xe c ko.

5.3.2 H thng phanh hai hoc nhiu ng (two-line or multi-line braking system): T hp trong

h thng phanh ca cc xe ring bit tc dng theo cch hai hay nhiu ng c dng mt cch

ring bit v ng thi cung cp nng lng v iu khin h thng phanh ca xe c ko.

5.3.3 H thng phanh lin hp (continuous braking system): S kt hp cc h thng phanh ca

cc xe trong on xe v c nhng c trng sau:

a) t gh li v bng tc ng n, ngi li c th iu chnh b phn iu khin tc ng trc tip

trn xe ko v iu khin phanh tc ng gin tip trn xe c ko;

b) nng lng dng phanh mi xe trong on xe c cung cp bi cng ngun nng lng (c

th l sc lc c bp ca ngi li);

c) phanh ca mi xe trong on xe l cng pha hoc hp pha.

5.3.4 H thng phanh bn lin hp (semi-continuous braking system): S kt hp cc h thng

phanh ca cc xe trong on xe v c nhng c trng sau:

a) t gh li v bng tc ng n, ngi li c th iu chnh b phn iu khin tc ng trc tip

trn xe ko v b phn iu khin tc ng gin tip trn xe c ko;

b) nng lng dng phanh mi xe trong on xe c cung cp bi t nht hai ngun nng lng

(mt trong chng c th l sc lc c bp ca ngi li);

c) phanh ca mi xe trong on xe l ng pha hoc hp pha.

TCVN 6821 : 2001

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5.3.5 H thng phanh khng lin hp (non-continuous braking system): S kt hp cc h thng

phanh ca cc xe trong on xe khng phI l lin hp hoc bn lin hp.

6 Cc nh ngha b sung

6.1 Cp; dy (cable; wire): Vt dn truyn dn nng lng in.

6.2 ng truyn dn nng lng

6.2. 1 ng (pipe): ng mm hoc cng dng truyn dn nng l ng kh nn hoc thy lc.

6.2. 1. 1 ng cng (rigid pipe): ng c hnh dng c nh ni hai phn c nh t ng i vi nhau.

Ch thch 12 - ng ni khng b bin dng c coi l c nh.

6.2. 1.2 ng na cng (semi-rigid pipe): ng c hnh dng khng c nh ni hai phn c nh

tng i vi nhau.

6.2. 1.3 ng mm (flexible pipe): ng c hnh dng khng c nh ni hai phn chuyn ng t ng

i vi nhau.

Ch thch 13 - ng cun l dng c bit ca ng mm.

6.2.2 Cc ng ca thit b phanh theo chc nng

6.2.2.1 ng cp (feed line): ng ni gia ngun nng lng hay bnh tch nng vi b phn iu

khin dng nng lng (v d, b phn ny c th l van phanh).

Ch thch 14 - nh ngha ny khng p dng cho ng ni hai xe trong on xe.

6.2.2.2 ng kch hot (actuating line): ng ni b phn iu khin dng nng lng (v d: van

phanh) vi b phn chuyn i nng lng ca tc nhn sang c nng (chng hn nh: xi lanh phanh).

6.2.2.3 ng dn (pilot line): ng ni mt b phn iu khin (v d: van phanh) vi mt b phn

iu khin khc (v d: van ngt), dng nng lng ch dng iu khin b phn iu khin th hai.

Ch thch 15 - nh ngha ny khng p dng cho ng ni hai xe trong on xe.

6.2.3 ng lin kt thit b phanh ca cc xe trong on xe

6.2.3.1 ng cung cp (supply line): ng cp c bit truyn nng lng t xe ko sang bnh

tch nng ca xe c ko.

TCVN 6821 : 2001

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6.2.3.2 ng iu khin (control line): ng dn c bit, nh nng lng cn thit iu

khin c chuyn t xe ko sang xe c ko.

6.2.3.3 ng cung cp v iu khin chung (common supply and control line): ng dng lm

ng cung cp cng nh ng iu khin.

Ch thch 16 - nh ngha ny p dng cho h thng phanh ng n.

6.2.3.4 ng d phng (secondary line): ng kch hot c bit truyn nng lng cn thit cho

phanh d phng ca xe c ko t xe ko sang xe c ko

6.3 Phanh iu chnh c (modulatable braking): Loi phanh, trong gii hn lm vic bnh thng

ca b phn iu khin, cho php ngi li bt k thi im no tng hoc gim lc phanh ti mc

tho ng bng tc ng ca b phn iu khin.

Khi tng lc phanh tng bng cch tc ng ln b phn iu khin, mt tc ng ngc li s lm

gim lc phanh (chc nng b tr n).

6.4 p lc

6.4. 1 p lc tc dng ban u ca m phanh (threshold pressure for application of brake

linings): p lc cn thit ban u ca cht lng cng tc to ra m men phanh c cu phanh

(xem hnh 1).

6.4.2 p lc cnh bo (warning pressure): p lc, di gi tr , b phn cnh bo hot ng.

6.4.3 p lc an ton (protection pressure): p lc c n nh trong mt phn ca h thng phanh

sau khi mt b phn khc hoc cc ph kin ca thit b phanh b trc trc.

6.4.4 p lc nh m phanh (release pressure of brake linings): p lc cn thit ban u ca cht

lng cng tc lm gim m men phanh (xem hnh 1).

6.4.5 p lc phanh tim cn (asymptotic pressure of braking): p lc phanh n nh sau khi b

phn iu khin tc dng hon ton: trong thc t, p lc tim cn t c mt khi p lc ny c

duy tr khng i trong 5 giy.

6.4.6 p lc gi phanh (hold-off pressure) (b kch hot c cu phanh l xo): p lc cn thit ban

u ca cht lng cng tc to ra m men phanh c cu phanh (xem hnh 2).

6.4.7 p lc bt u nh phanh (commencement of release pressure) (b kch hot c cu phanh

l xo): p lc ban u ca cht lng cng tc cn thit lm gim m men phanh (xem hnh 2).

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6.4.8 p lc nh phanh hon ton (full brake release pressure) (b kch hot c cu phanh l xo):

p lc ca cht lng cng tc trong bung nn l xo ti m men phanh tin ti gi tr 0 (xem hnh 2).

6.4.9 p lc nn l xo hon ton (full spring compression pressure) (b kch hot c cu phanh l

xo): p lc cn thit ca cht lng cng tc trong bung nn l xo y l xo (p) n v tr tn cng

ca n (Hnh 2).

p lc nh m phanh (6.4.4)

M

men

pha

nh

0 p lc

p lc tc dng ban u ca m phanh (6.4. 1)

Hnh - 1

M

men

pha

nh

p lc bt u nh phanh (6.4.7)

p lc nh phanh hon ton (6.4.8)

0 p lc

p lc g phanh (6.4.6)

Hnh - 2

6.5 B phn cnh bo (warning device): B phn bng m thanh hoc hnh nh bo cho ngi li

bit (cc) h thng phanh ht k hot ng hay cn bo dng.

p lc nn l xohon ton (6.4.9)

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6.6 C cu tc dng (application mechanism): Tt c cc thnh phn c kh ca b phn truyn

ng ni b phn tc ng (nh xi lanh...) vi c cu phanh.

6.7 B phn b mn; b iu chnh c cu phanh (wear compensasion device; brake adjuster):

B phn mt cch t ng hay bng cch khc b lp s mn ca m phanh i vi c cu phanh ma

st (c cu phanh tang trng hoc c cu phanh a).

6.8 B phn nh ph tr (auxiliary release device) (b kch hot c cu phanh l xo): B phn cho

php kh lc phanh khi p lc cung cp gim thp hn p lc nh hon ton do, v d nh, b kch hot

c cu phanh l xo b hng.

6.9 B phn cn bng lc phanh (braking force proportioning device): B phn c chc nng bin

i lc phanh mt cch t ng hay bng cch khc.

6.9.1 B phn cm ng ti trng (load-sensing device): B phn t ng iu chnh lc phanh trn

mt hay nhiu bnh xe theo ti trng tnh hoc ng t ln (cc) bnh xe.

6.9.2 B phn cm ng p lc (pressure- sensing device): B phn t ng Iu chnh lc phanh

trn mt hoc nhiu bnh xe tu theo p lc u vo.

6.9.3 B phn cm ng gim ga (deceleration-sensing device): B phn t ng Iu chnh lc

phanh trn mt hoc nhiu bnh xe ty theo s gim ga ca xe.

7 C hc phanh

7.1 C hc phanh (braking mechanics): Hin tng c hc din ra t lc bt u tc ng ln b

phn iu khin n khi kt thc tc ng phanh.

7.2 Hin tng tr ca h thng phanh (braking system hysteresis), Fc: S khc nhau gia cc

lc iu khin khi tc dng v nh phanh vi cng mt m men phanh (xem hnh 3).

7.3 Hin tng tr ca c cu phanh (brake hysteresis), Fs: S khc nhau gia cc lc tc dng

khi tc dng v nh phanh vi cng mt m men phanh (xem hnh 4).

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M

men

pha

nh

M

men

pha

nh

FS FS

Lc iu khin Lc tc dngHnh - 3 Hnh - 4

7.4 Cc lc, m men

7.4.1 Lc iu khin (control force), Fc: Lc t ln b phn iu khin.

7.4.2 Lc tc dng (application force), Fs: i vi c cu phanh ma st, l tng lc tc dng ln mt

cm m phanh, gy ra lc phanh do hiu ng ma st (xem cc v d in hnh trong ph lc A).

7.4.3 Tng lc phanh (total braking force), Ft: Tng ca cc lc phanh ti cc b mt tip xc gia

tt c cc bnh xe vi b mt ng, c to ra do tc dng ca h thng phanh chng li s chuyn

ng hoc xu hng chuyn ng ca xe.

7.4.4 M men phanh (braking torque): Sn phm ca cc lc ma st, c to ra do lc tc dng

mt c cu phanh v khong cch gia im t ca cc lc ny vi trc quay.

7.4.5 B phanh (brake drag): Hin tng m men phanh c th vn tn ti sau khi b phn iu

khin tr li v tr nh.

7.4.6 Phn b phanh (lc phanh); t s phanh Anh, cn bng phanh M [braking (brake force)

distribution; braking ratio GB; brake balance US]: Gi tr th hin t l phn trm i vi mi trc

bng t s gia lc phanh ca mi trc v tng lc phanh (v d: 60% cu trc v 40% cu sau).

7.4.7 Cc h s khuych i c cu phanh (Brake amplification factor)

7.4.7.1 H s c cu phanh (bn ngoi) [brake factor (external)], C: T s gia lc/m men phanh

u ra v lc/m men u vo c cu phanh.

7.4.7.2 H s c cu phanh (bn trong) [brake factor (internal)], C*: T s gia tng lc tip tuyn

ti bn knh hiu dng ca mt c cu phanh v lc tc dng, Fs.

TCVN 6821 : 2001

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Ch thch 17 - C* l tng cc h s guc phanh ch trong trng hp cc lc tc dng cn bng nhau.

Ch thch 18 - V d in hnh ca gi tr C* l h s ma st c th hin trn hnh 5 v cc v d tnh

ton ca C* c trnh by trong ph lc A.

H

s c

c

u ph

anh

C* 10

1 9

8 2 7

6

5 4 1 C cu phanh t cng ha

3 3 2 C cu phanh kp

(xem ch thch 1 trong bng A.2)

2 4 3 C cu phanh n

1 (xem ch thch 1 trong bng A.2)

4 C cu phanh a 0,1 0,2 0,3 0,4 0,5 0,6 0,7

H s ma st Hnh - 5

7.4.7.3 H s guc phanh (shoe factor), SF: T s gia lc tip tuyn v lc tc dng trn cng mt

cm m phanh tang trng.

7.4.7.4 H s guc phanh trung bnh (mean shoe factor), MSF: T s gia tng cc h s guc

phanh ca mt c cu phanh v s cm m phanh tang trng.

7.5 Thi gian

Cc khong thi gian khc nhau c nh ngha theo biu l tng trn hnh 6.

7.5.1 Thi gian tc dng ca b phn iu khin (control device application time): Khong thi

gian nm gia t3 v t0.

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S0

Kho

ng

cch

Thi gian

V0 1

a0 2

3

4

t0 t1 t2 t3 t4 t5 t6 t7 Thi gian

1 Vn tc xe; 2 Gia tc phanh; 3 p lc ng ng; 4 Hnh trnh iu khin;

t0 Thi im ngi li bt u kch hot b phn iu

khin, ngha l thi im iu khin phanh bt u

dch chuyn.

t1 Thi im p lc trong ng ng bt u tng.

t2 Thi im gia tc phanh t n gi tr n nh

t3 Thi im b phn iu khin t n v tr gii hn.

t4 Thi im hai ng thng vn tc xe giao nhau

(nh trn biu ).

t5 Thi im p sut ng ng t n gi tr n

nh.

t6 Thi im gia tc phanh t n gi tr n nh.

t7 Thi im xe dng li.

Hnh - 6

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7.5.2 Thi gian phn ng ban u (initial response time): Khong thi gian nm gia t1 v t0

7.5.3 Thi gian tch ly (buildup time): Khong thi gian din ra gia t5 v t1.

7.5.4 Thi gian phanh tc dng (active braking time): Khong thi gian din gia t7 v t2

7.5.5 Tng thi gian phanh (total braking time): Khong thi gian din ra gia t7 v t0.

7.6 Khong cch (qung ng)

7.6.1 Qung ng phanh (braking distance) S1: Qung ng xe tri i trong thi gian phanh tc

dng.

7.6.2 Khong cch dng (stopping distance) S0: Qung ng xe tri i trong ton b thi gian

phanh (tc l khong cch c tnh t thi im ngi li bt u kch hot b phn iu khin cho

n thi im xe dng li).

7.7 Cng phanh (braking work) W: Tch phn ca tng lc phanh tc thi Ft v dch chuyn vi phn

ds trn qung ng phanh s:

s

W = dsF f 0

7.8 Cng sut phanh tc thi (instantaneous braking power) P: Tch s gia tng lc phanh tc

thi Ft v vn tc xe v.

P = Ff v

7.9 Gia tc phanh (braking deceleration): S gim vn tc t c nh h thng phanh trong thi

gian ang xt, t.

7.9.1 Gia tc phanh tc thi (instantaneous deceleration), a:

a = dtdv

Ch thch 19 - Trn ng cong gia tc phanh a(t) b qua nhng mp m th cp.

7.9.2 Gia tc phanh trung bnh trn khong cch dng (mean deceleration over stopping

distance), ams:

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ams = 0

20

2SV

trong V0 l vn tc ca xe ti thi im t0

7.9.3 gia tc phanh trung bnh gia hai thi im bt k (mean deceleration between any two

instants), amt:

amt = ij

ji

ttVV

trong Vi v Vj l cc vn tc ca xe tng ng ti cc thi im ti v tj.

Ch thch 20 - Cng thc ny c th c dng nh gi, v d nh hiu qu phanh ca cc b hm chm

dn.

7.9.4 Gia tc phanh khai trin y trung bnh (mean fully developed decelaration), amft : Gi tr

trung bnh ca gia tc phanh theo thi gian ca gia tc khai trin y (t7-t6).

amft =

7

667

1 ttadt

tt

Ch thch 21 - Theo cng thc ny, khng c mi lin h trc tip gia khong cch dng v gi tr ca gia

tc phanh khai trin y trung bnh.

7.10 Lc phanh ring (braking rate), z

(1) T s gia tng lc phanh Ft v lc Gs tng ng vi tng khi lng tnh trn (cc) trc ca (cc)

xe:

z = s

f

GF

(2) Ngoi tr trng hp ca bn moc, t s gia gia tc phanh xe a v gia tc trng trng g (gia

tc ri t do):

z =ga

8 B phn chng hm cng (anti-lock device or anti-lock braking system), ABS

8.1 B phn chng hm cng (antilock device): B phn t ng iu chnh trt, theo hng

quay ca bnh xe, trn mt hoc nhiu bnh xe trong khi phanh.

8.2 Cc thnh phn ca b phn chng hm cng

8.2.1 Cm bin (sensor): Thnh phn c nhim v nhn bit trng thi quay ca (cc) bnh xe hoc

trng thi ng lc ca xe v truyn thng tin ny n b iu khin.

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8.2.2 B iu khin (controller): Thnh phn c nhim v nh gi thng tin do (cc) cm bin cung

cp v truyn lnh n b iu bin.

8.2.3 B iu bin (modulator): Thnh phn c nhim v iu chnh p lc to ra lc phanh theo lnh

nhn c t b iu khin.

8.3 Cc dng iu khin bnh xe

8.3.1 iu khin bnh xe n (individual wheel control): iu khin trong p lc to ra lc

phanh trn tng bnh xe c iu chnh ring r.

8.3.2 iu khin nhiu bnh xe (multi-wheel control): iu khin trong p lc to ra lc phanh

mt cm bnh xe c iu chnh bng mt lnh chung.

8.3.2.1 iu khin trc (axle control): iu khin nhiu bnh xe trong cc bnh xe trn mt trc

c iu khin bng mt lnh chung.

8.3.2.2 iu khin bn (side control): iu khin nhiu bnh xe trong cc bnh xe mt bn xe

c iu khin bng mt lnh chung.

8.3.2.3 iu khin cho (diagonal control): iu khin nhiu bnh xe trong cc bnh xe i din

cho nhau c iu khin bng mt lnh chung.

8.3.2.4 iu khin nhiu trc kt hp (combined multi-axle control): iu khin nhiu bnh xe

trong tt c cc bnh xe ca mt cm trc c iu khin bng mt lnh chung.

8.3.3 La chn tn hiu cm bin cho iu khin h thng

8.3.3.1 La chn bin i

8.3.3.1.1 La chn thp (select-low): iu khin nhiu bnh xe, y tn hiu ca bnh xe u tin

c xu hng b hm cng s iu khin h thng tt c cc bnh xe ca cm bnh xe.

8.3.3.1.2 La chn cao (select-high): iu khin nhiu bnh xe, y tn hiu bnh xe cui cng

c xu hng b hm cng s iu khin h thng tt c cc bnh xe ca cm bnh xe.

8.3.3.2 La chn xc nh trc

8.3.3.2.1 La chn theo bnh xe (selection by wheel): iu khin nhiu bnh xe trong tn hiu

ca mt bnh xe nh trc s iu khin h thng tt c cc bnh xe ca cm bnh xe.

8.3.3.2.2 La chn trung bnh (average selection): iu khin nhiu bnh xe trong tc tc thi

ca mt vi bnh xe c ly trung bnh v l tn hiu dng iu khin h thng tt c cc bnh xe

ca cm bnh xe.

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8.4 Nhng nh ngha lin quan ti hot ng iu khin

8.4.1 Vn tc iu khin ti thiu (minimum cotrol speed): Vn tc ca xe m nh hn b phn

chng hm cng khng cn kh nng thng c cc lc iu khin ca ngi li c truyn ti cc

c cu phanh.

8.4.2 Tn hiu cm bin (sensor signal): Thng tin do cm bin cung cp.

8.4.3 Gii m xung cm bin vn tc bnh xe (resolution of impulse wheel speed sensor): S

lng cc xung do cm bin cung cp trong mt vng quay ca bnh xe.

8.4.4 Chu k iu khin (control cycle): Mt chu k khp kn ca chc nng b phn chng hm

cng t mt ln hm cng bnh xe sp din ra n ln tip theo.

8.4.5 Tn s iu khin (control frequency): S lng chu k iu khin din ra trong mt giy trn

mt ng ng u.

9 Cc thnh phn ca c cu phanh v th m phanh

9.1 Cm m phanh (brake lining asembly): Thnh phn ca c cu phanh tang trng hay c cu

phanh a c p t vo tang trng hay a phanh to ra lc ma st.

9.1.1 Cm m phanh tang trng (lined shoe asembly): Cm m phanh ca c cu phanh tang

trng.

9.1.1.1 Cm m phanh dn (leading shoe asenbly) Cm m phanh tang trng trong hiu qu ca

lc tc dng tng ln do lc ma st c to ra gia tang trng ang quay v m phanh.

9.1.1.2 Cm m phanh b dn (trailing shoe asembly): Cm m phanh tang trng trong hiu qu

ca lc tc dng gim i do lc ma st c to ra gia tang trng ang quay v m phanh.

9.1.2 Cm m phanh a (pad assembly): Cm m phanh ca c cu phanh a.

9.2 Gi (attachment or carrier): Thnh phn ca cm m phanh m m phanh ma st c gn

vo .

9.2.1 Guc phanh (shoe): Thnh phn ca cm m phanh tang trng m phanh.

9.2.2 Tm (pha sau) (backplate): Thnh phn ca cm m phanh a m phanh.

9.3 M phanh (brake lining): Phn vt liu ma st ca cm m phanh.

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9.4 Bin dng m phanh (lining profile): ng vin bao quanh vng b mt ch st ca m phanh.

9.5 Biu hin b mt ca m phanh

9.5.1 nh bng (glazing): Trng thi b mt m phanh ging nh knh.

Ch thch 22 - nh bng ngha l s gim h s ma st v thng gn lin vi ch ti nh.

9.5.2 S bong tch (detachment): S tch ri ca vt liu m phanh khi gi ca n.

9.5.3 Nt (crack): Vt nt su v hp trn b mt m phanh khng ph v vt liu m phanh

thnh hai hay nhiu mnh.

9.5.4 Nt b mt (surgace crack): Vt nt nng trn b mt, thng xut hin thnh nhiu vt trn

cng mt m phanh.

9.5.5 S bong chc (flaking): S tch ri ca cc mnh nh vt liu m phanh.

9.5.6 Vt kha (scoring): Cc rnh trn b mt, thng song song vi hng ma st.

9.6 Th m phanh

9.6.1 R m phanh hay nh bng m phanh (lining bedding; burnishing US): Phng php th

t c mc tng thch xc nh v hnh hc, vt l v ho hc gia b mt m phanh v tang

trng hoc a phanh.

9.6.2 Th m phanh ngui (cold lining test): Th c thc hin theo qui trnh nh xc nh

hiu qu phanh ca m phanh nhit phanh ban u nh hn mt gi tr cho trc.

9.6.3 Th m phanh nng (hot lining test): Th c thc hin theo qui trnh nh xc nh

hiu qu phanh ca m phanh nhit phanh ban u ln hn gi tr cho trc v ln n gi tr ln

nht nh.

9.6.4 Th ph hy (ca hiu qu m phanh) [fade test (of lining effectiveness)]: Th theo qui trnh

nh gm mt hoc nhiu ln tc dng phanh trn m phanh chu nhit.

Ch thch 23 - Khng nn nhm ln th ph hy vi s mt hiu qu do cc yu t nh s gin n m phanh.

9.6.5 Th phc hi (ca hiu qu m phanh) [recovery test (of lining effectiveness)]: Th c

thc hin theo qui trnh nh gm mt lot cc tc dng phanh xc nh kh nng phc hi ca

m phanh sau khi hiu ng nhit c to ra do th ph hy.

9.6.6 Th hiu qu m phanh sau khi th ph hy v phc hi (lining effectiveness test after

fade and recovery): Th c thc hin theo mt qui trnh nh xc nh hiu qu phanh ngui

ca m phanh tip theo th ph hy v phc hi nng.

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9.6.7 Th mn m phanh (lining wear test): Th c thc hin theo qui trnh nh xc nh

sc chu mi mn ca m phanh.

10 Trng thi phanh xe

10.1 Phanh khng u (uneven braking): trng thi c trng ca xe trong qu trnh tc dng

phanh c xu hng lch khi hng i thng sang phi hoc tri hoc hng i khng n nh trong

mt ln phanh.

10.2 X lch tri hoc phi (right or left pulling): xu hng xe lch khi hng i thng sang phi

hoc tri trong khi phanh.

10.3 Rung ng v n

10.3.1 Lc, rung (judder): rung ng xa xe tn s thp gy ra do qu trnh phanh m ngi li

nhn bit c nhng khng nht thit phi km theo nhng tc ng ca m thanh.

10.3.2 Chm ln (grabbing): hin tng khng u, khng mong mun ca m men phanh, nhng

khng nht thit phi nghe thy c.

10.3.3 Ting rt (squeal): m thanh gn nh trong c tn s cao v trn thc t khng i.

10.3.4 Ting kt (chirp): m thanh c bin thay i v c tn s t trung bnh n cao.

10.3.5 Ting r (twitter): m thanh c tn s t trung bnh n cao ging nh ting kt nhng ngt

qung v c tn s ngt qung cao hn tn s thay i ca ting kt.

10.3.6 Ting kn kt (grating): m thanh khng trong c tn s cao.

Ch thch 24 - y l ting ku phanh in hnh ca xe ray.

10.3.7 Ting gm (growl; groan US): m thanh khng trong, khng ko di, tn s tng i thp.

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Ph lc A

(qui nh)

V d v cc i lng tc dng phanh

A.1 Cc k hiu

K hiu M t

FS Lc tc dng ln nh guc phanh

FSL Lc tc dng ln nh guc phanh dn

FST Lc tc dng ln nh guc phanh b dn

FSD Lc tc dng ln guc phanh a ca cm mt vt

FW Lc tc dng ln mt vt ca c cu phanh mt vt

FTL Lc bin ca cm m phanh dn

FTT Lc bin ca cm m phanh b dn

FTP Lc bin ca cm m phanh s cp

FTS Lc bin ca cm m phanh th cp

FTD Lc tip tuyn ti bn knh tc dng ca mt cm m phanh phanh a

TOUT M men u ra ca c cu phanh

TIN M men u vo (trc cam) c cu phanh

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A.2 V d ca cc h s khuych i c cu phanh

Loi c cuphanh (1) Minh ha

H s c cu phanh (bntrong) (2)

C*

(7.4.7.2)

H s guc phanh trungbnhMSF

(7.4..7.4)

H s c cuphanh (bn

ngoi) (2)

C(7.4.7.1)

n

FTL

FS

FS

FTT

FTL + FTTC* = FS

Gi tr thng thng: 2.2

FTL + FTTMSF = 2 FS

Gi tr thng thng: 1,1

Kp v hai

chiu kp

FTL

FS

FS

FTL

2 FTLC* = FS


FTLMSF = FS


a

FTD + FTD FSD FSD

Bn knhhiu dng

FTDC* = 2 FSD


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Cng ho

mt/hai

chiu

FTP

FS

FTS

FTP + FTSC* = FS


Cam hnh

ch "S"

FTL

FSL FTL FTT

FSL FST

FST

FTT

2 (FTL + FTT)C* = FSL + FST

Gi tr thng thng: 2

TOUTC = TIN

Gi tr thngthng: 10

Mt vt n

FTL

FS

FW

FS

FTT

FTL + FTTC* = FS


FTL + FTTMSF = 2 FS


FTL + FTTC= FW

Gi tr thngthng: 14

TCVN 6821 : 2001

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Mt vt kp

hai chiu

FTL

FS

FW FW

FS FTL

2 FTLC* = FS


FTLMSF = FS


2 FTLC= FW

( loi thngthng)

Gi tr thngthng: 20

Ch thch - (1) "n" ni n phanh tang trng dn-b dn

"Kp" ni n phanh tang trng hai guc dn

"Mt chiu" ni n mt chiu quay ca tang trng

"Hai chiu" ni n c hai chiu quay ca tang trng

(2) Nhng gi tr thng thng c a ra trong bng A.1 i vi h s ma st ca m phanh xp x 0,4. Cc gi tr gii hn thng c gim i.

Phng tin giao thng ng b -3 Thit b v cc h thng phanhHnh - 6

tam.pdfPhng tin giao thng ng b -3 Thit b v cc h thng phanh

BIA TC 6821.pdfLi ni u

tcvn6821 2001.pdf phanh Ôtô

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