DE2102144C3 - Brake valve for hydraulic trailer braking systems - Google Patents

Description

3 4

contrary to the action of a hydraulic cylinder between him and a working cylinder Hcbcvornclviujg.

screwed into the valve body, screwing in its input on connection 9, the annular chamber 10, 14 _undI Kan ^ adjustable valve cover prestressed The annular chamber 11 it istüb R ^{ddl. a} '"^ ^r .% _ver .

th pressure limiting spring with the, - «controlled with an axial bore 17 in the» enuisui -

Actuating pressure is applied and also at 5 bound, in which a plunger l »« ⁿ ™ ^u "' _Vem = _ü _

Overcoming the spring preload supported by the one valve cover 19 ^lsl - ^u _hjeb .

controlled actuation pressure is displaceable and slide 2 is against a backstop «·

with this shift frictionally with dtm beta bar. Channel 12 is on the one hand with the * "« "" *

servicing piston is connectable, this through the brake 8, on the other hand via a «romreg · ^ ^

Pressurization acting on the relief member> ° a return tank 22 in ^Ve _D ^r ° ¹ ™ |; _p V; _: j _{older 2} 1

power in the sense of canceling the actuating consumer 13 is indicated by the * f ^ ™^ ^ _3ηπ -

eungskraft can be relieved. in connection. The current regulator 21 * "* £ ™ ^a ™ _

'As a result, on the one hand, the valve slide is through the way to maintain a Drurtmi «^

the actuating piston can be actuated directly and flow from the annular chamber iu to ο fc

on the other hand, the pretensioning of the pressure limiting spring with the connection of the ^R ' ⁿ S « ^m ™" J?, _mö ".

the one that determines the maximum brake pressure, on the one hand, a regulation of the brake speed «1 5

is borrowed by screwing in or unscrewing the valve cover and on the other hand the brake cylinder β

adjustable return 22 to connect. . -,

Appropriate trip is the relief member with the actuation piston 3, whose AbstuteNacne

the actuating pressure can be acted upon directly. * ° for the purpose of a coaxial transmission of the actuation

It is advantageous if the relief member ^acts as a force on the valve slide 2 ^ka ! ° ttenf ° ™ \ ^a "* f _al

form a sealed, axially displaceable guide sleeve! is, is in a ^housing ^ _r ^h ™ "| ^ £ _a

is designed in which the piston rod of the actuator to the valve slide 2 is displaceable und1 weis em

supply piston is sealed coaxially displaceable. Piston rod 25 on. which in a, ^ " ^1α ' ^{1ί1 m} , such that when overcoming the spring preload, 5 housing bore 24 axially displaceable, as, hnua

the guide sleeve on the stop with a suture? stungs member serving leadership sleeve -f> axial

the guide sleeve on the stop gg

the piston rod comes. is slidable.

In a further embodiment according to the invention, the guide sleeve 26 is against a>

the relief member via a frictional connection with it 27 through a compression spring 2

sig connectable auxiliary piston with the actuating 3 ° prints, which between the ^huhru "^g;""vV

dfuck can be acted upon indirectly. one in the valve housing 1

dfuck can be acted upon indirectly. g ^^ / S.

It is useful here if the relief part cover 29 is pretensioned. JJ «™ ^ ^S 3er ₂₈

died as an axially displaceable, from the Druckbe- guide sleeve 26 and the ^D ^^ Sf _ung 4 In

The limiting spring surrounded by the auxiliary piston form the brake pressure limiting device «B;

axially penetrated spring cup is formed. of 35 of the housing bore U Ms: erne ^ "™ X _ns3

when overcoming the spring preload with end faces 31. 32 of the J ^ ™ ^ ⁸ _{d through}

take through the auxiliary piston to the stop with or the guide sleeve Mabgesc ^ "^ ^Γ

an approach to the koaxia.en actuating piston density 33. ^^^

It is also provided according to the invention that 40 piston «3 or the

the closing 35, ", t" "^ SSÄf

Effective surfaces of the actuating piston and the discharge from the tractor brake valve

power link or the force-locked ^connection with it Schle PP ^ ^brake i ₇ ^mc \ ^be X'teft between the leadership

bindable auxiliary piston a joint, with which the rel.tive ^^^ SjfS Ts through

Actuating rtrudt pressurized valve chamber ab- 45 rungshulse 26 and the ^ piston ⁵ ^ _d -

close These active surfaces are advantageously a '"" JaK An «wag mr

the same size. Guide sleeve 26 in the ends of the spring «8» «f ™ ^.

The following are two exemplary embodiments of the jmsvent is g

SS ^{hf di ZeiChnUng Nä} SS S ^ "S ^ fish

_F trdn! Sngsge _m äßes trailer brake valve ? * ^^ ff ^ t? £

til, the relief member of which with the actuation 1 η of the valve chamber * ° ₂₀ .

pressure can be applied directly. in longitudinal section, the valve ^{slide 2 through the dl} J «ucMieni

2 shows a partial section through a further training of ^Ste represented ^"un S |. ^ ^{3" ε} ^ _η ^ 'J ^^ s the

management of the trailer brake valve according to Fig. I, 55 slide position .M d «V ^^ 7 ™ that

whose relief link with the pump actuation pressure? and de ^m Consumer ™ ξ>

can be acted upon indirectly via an auxiliary piston. this by the ^ ^m pf! ^m "^ J _{n the} f *

The trailer emergency valve shown in Fig. 1 is, while the connection ^zw '™ ^a £ \ ™ Autovermietung ^P _that

has a two-part valve housing 1, in which one and the trailer brake 8 is closed, st,

Valve slide 2, a serving as an actuator 60, the trailer brake is released.

Beffltigungskolben 3 and a Bremsdruckbegren- W ^ f ^ gSTS emenf dem

ignition device 4 are arranged. ^ brake pressure corresponding actuation

The valve slide 2 controls the tractor brake pressure enisp 5 with control edges 5,6

the connection between a pressure acting as a pressure medium source is applied to the cUe ^ ™ »« ne

serving pump? and a trailer _{brake8 6 5} actuating piston3 ^ and ^ ™ ^ ™ _n ^C " _{spring M}

Via connection 9, annular chambers 10 11 and channel 12 ™ ££ ™ ^ ™ * £ 2 ^ becomes effective here

as well as the connection between the pump 7 and loaded ^ ^hru £ ^u '^ _{ülse 26 acting pressure}

another consumer 13, for example one is the aut die t-unrungsiiuisc

5 6

impact force against the force of the pressure limit pressure acting on the slide surface 37 Tung spring 28 directed, however, this initially pressurizing force cannot act on the valve rail overcome. Over 2 acting actuating force overcomes, so that

The valve slide 2 is moved back up again by the actuation of the valve slide 2 piston 3 against the return spring 20 according to FIG. 5 and thereby the connection between the ring chambers Actuators 10 and 21 acting on actuation piston 3 interrupts. This achieves supply pressure shifted, whereby the control edge 6 that also in this case the trailer brake pressure the connection between the annular chambers 10 and depending on the actuation pressure and thus 14 throttles, while the control edge 5, the connection from the Schlcppcrbrcmsdruck, but regardless of manure between the annular chambers 10 and 11 releases. io consumption pressure, controlled and on an agreed-here it is assumed that the consumer th, dependent on the spring preload maxima-13 is not in operation, so that the value of the pump 7 is limited.

The working fluid supplied is almost unpressurized via the brake control valve according to FIG. 2

the consumer 13 to the return tank 22 is only called from the Brcmsstcucr \ tntil according to FIG. 1. The throttle 15 caused by the valve layer 2 through a different design of the actuating member development of the connection between the annular chambers 10 and the brake pressure limiting device,
and 14 and thus "the connection between which the brake pressure extension device 4 has

The pump 7 and the consumer 13 have the spontaneous generation of an axially unified dynamic pressure in the annular chamber 10 and thus a sliding Fcdcrtopl 40, which is used by the pressure leg of the annular chamber 20, which is now connected to it, and which is bypassed by the pressure leg of the annular chamber 20, and this leads to 11 . As a result, on the one hand, the housing extension 27 is pressed. The spring cup 40 häneerbrcmsc 8, on the other hand that of the plunger, is penetrated by a coaxial auxiliary piston. 18 Γη of the bore 17 closed chamber under the pressure in a bore 42 in the valve cover 29 occupied, whereby a seal is guided in the trailer brake 8 and a piston attachment 43 can be positively connected to the spring cup 40 above the actuating pressure of the trailer 25. brake pressure is effective, which simultaneously acts on the Schic- The coaxial / around spring cup 40 and to the auxiliary piston surface 37 and the valve slide 2 41 arranged actuating piston 3 has on the periphery of the control position assumed by this in the catch evenly distributed piston lugs 43, which are in equilibrium with the opposite Actuate slots 45 in the spring cup 40 protrude.
guncskraft holds. 30 Since holes 24 and 42 have the same diameter

If the actuation pressure reaches a value at which knives have, also with this version the the Druckbcauf- Bremsslcuervcntils acting on the Führhülsc 26 the housing chamber 30 knockdown force the bias of the pressure-limiting active surfaces 31 and 46 of the actuating spring 28 overcomes, the guide sleeve supply piston 3 or the auxiliary piston 41 is the same size 26 moved so far relative to the piston rod 25, 35 dimensioned.

until it hits the stop on the piston rod. The brake pressure control valve works as shown in Fig. 2

25 seated spring ring 36 comes. The guide as well as the brake pressure control valve according to sleeve 26 and the actuating piston 3 are now Fig. 1. with the only difference that the Bokraflschlüssig connected to each other, so that the opening of the housing chamber 30 with the actuator Guide sleeve 26 acting force, the spring loading force from the pressure of the pressure relief member and spring preload results in 40 with the actuation thickness not directly, dismantled. also on the actuating piston 3 contrary to the indirectly via the frictional connection with it this acting Beiaktivkraft becomes effective. bound auxiliary piston 41 is applied and that This enables further actuation of the valve when the maximum trailer slide is exceeded 2 in the sense of a further operating pressure 45 l'isniNuruck corresponding actuation pressure Prevents rise and thus a limitation of the auxiliary piston 41 overcoming the spring cup 40 Trailer braking pressure as a function of the preload of the pressure limiting spring 28 The preload of the pressure-limiting spring 28 takes with it until the spring cup 40 comes to a stop with it suffices. the piston lugs 44 of the actuating piston 3

It is now assumed that when you press the 5 ° comes. This is like the brake control valve Schleppcrbrcmsventils the consumer 13 in the loading according to FIG. 1, a further actuation of the valve drive is and that between the pump 7 and the slide 2 in the sense of a further increase de * Consumer 13 a certain pressure is present. Trailer brake pressure prevented and thus a If this pressure is lower than that for braking the limitation of the trailer braking pressure in the trailer required trailer brake pressure, so that the preload of the pressure limitation works then the brake control valve spring 28 according to the invention is reached.

til also, as already described, with the only one. This bias is both in the execution

Difference, that by the throttling of the Vcr- according to F i g. 1 as well as in the execution Connection between pump 7 and consumer 13 is fig. 2 by screwing in or unscrewing the valve dec generated dynamic pressure only the difference between the elbow 29 or by inserting a pad desired trailer brake pressure and the disc between the pressure relief spring and the valve needs to meet consumer pressure. tildcckel easily adjustable.

On the other hand, if the consumer pressure is higher than the pressure of the actuating piston3 the valve slide;

The required for braking the trailer is directly actuated in the braking according to the invention hangerbrcmsdruck. This is how the control valve works, the accuracy of the brake pressure control appropriate Brcmsstcucrvcntil as a pressure relief valve not otherwise due to manufacturing tolerances til, in such a way that when the dcnj is exercised, the intermediate links are impaired. Beyond that Actuating the appropriate trailer brake is both a perfect operation of the Be! Äti

piston as well as a precisely coaxial transmission the actuating force on the valve slide guaranteed.

The execution according to FIG. 1 is characterized by a particularly simple structure. On the other hand

The embodiment according to FIG. 2 is shown in that, during normal actuation of the trailer brake, the actuating piston is only displaced against the frictional resistance of a single seal.

1 sheet of drawings

Claims (6)

pressurizable valve chamber (30) Claims: close. 7. Brake valve, according to one or more of the I. Brake valve for hydraulic trailer claims 1 to 6, characterized in that bremsanlagcn with a valve slide for 5 which can be acted upon with the actuating pressure control of the connection between a pressure active surfaces (31, 32 or 46) of the actuating piston. medium source and the trailer brake as well as between (3) and the relief member (26) or the see the pressure medium source and at least with this non-positively connectable auxiliary column of a further consumer, such that the indicator (41) are of the same size,
hängerbrcmsdruck independent of the ver io
pressure is controllable, the valve slide duich an axially guided and with the actuating pressure which can be acted upon in the brake valve can be actuated is that with a preloaded pressure 15 The invention relates to a brake valve limiting device cooperates, therefor hydraulic trailer brake systems with a characterized in that the actuator valve slide for controlling the connection zwigungskolben (3) directly on the valve slide (2) see a pressure medium source and the trailer is in contact and the Bremsdruckbegrenzungseinrich- 20 brake and between the pressure medium source and device (4) a relief member (26 or 40) on at least one other consumer, such that shows that contrary to the effect of between the Anhäiigerbrcmsdruck regardless of Verihm and a user pressure in the valve housing (1) can be controlled, the valve screw adjustable in its screw-in section by means of an axially guided and with the in the ren valve cover (29) preloaded pressure control valve controlled actuating pressure limiting spring (28) can be actuated with the actuated actuating piston which can be actuated and which can be actuated with The pressure is applied and that is also overcome with a preloaded pressure limiting spring the spring preload controlled by the holding brake pressure limiting device Actuating arm k is displaceable cooperates. and serve with this shift positively with 30 trailer brake valves of this type the actuating piston (3) can be connected, the trailer braking pressure as a function of this this by the pressure on the relief member (26 preferably used as actuation pressure or 40) acting pressure application force in the brake pressure in the tractor but independent of the In the sense of a cancellation of the actuation force, the pressure is fed via the trailer emergency valve is resilient. Control 35 consumers. This consumer can 2. Brake valve according to claim 1, characterized, for example, a power steering or a hydraulic system, that the relief member (26) be with see lifting device. The brake pressure limiting Actuating pressure can be acted upon directly. The switch mechanism ensures that the trailer 3. Brake valve according to claim 2, characterized in that the brake pressure does not have a certain maximum value indicates that the relief member exceeds 40 as a. sealed axially displaceable guide sleeve In a known trailer brake valve this (26) is formed, in which the piston rod (25) type is the valve slide by an actuating of the actuating piston (3) sealed coaxially supply piston via one on this between two is displaceable in such a way that when overcoming the spring plates prestressed pressure limiting spring Spring preload the guide sleeve (26) can be actuated at 45 (French patent 1450 557). It is a disadvantage of this valve that the piston stops with a shoulder (36). that the actuation rod comes. supply piston the valve slide over a number 4. Brake valve according to claim 1, thereby actuated intermediate members, their manufacturing tolerances indicates that the relief member (40) leg one on the accuracy of the brake pressure control with it positively connectable auxiliary 50 pregnant. piston (41) indirectly with the actuating pressure is. boundary spring and thus the maximum trailer 5. Brake valve according to claim 4, thereby not adjustable brake pressure. The well-known valve indicates that the relief member as a also has the disadvantage that it becomes a axially displaceable, from the pressure limiting 55 tilting of the actuating piston or to a spring (28) surrounded and by the auxiliary piston (41) uneven loading of the valve slide coaxially penetrated spring cup (40) designed with the actuating force can come. That is, when overcoming the spring preload, the object on which the invention is based tion with entrainment by the auxiliary piston to avoid disadvantages and a brake valve of a stop to create with an approach (44) on the category mentioned above that one of axial actuating piston (3) comes. Intermediate links unimpaired and therefore safe 6. Brake valve according to one or more of the safe and precise actuation of the valve slide so-claims 1 to 5, characterized in that as an easily adjustable limitation of the maximum guaranteed with the actuation pressure can be acted upon by len brake pressure. Active surfaces (31, 32 or 46) of the actuating piston 65 This object is achieved according to the invention bens (3) and the relief member (26) or the solved that the actuating piston directly on the with this positively connectable auxiliary piston valve slide and the brake pressure limiting bens (41) has a joint with the actuating device a relief member which