DE1751956A1 - Pressure control valve - Google Patents

Pressure control valve

Info

Publication number
DE1751956A1
DE1751956A1 DE19631751956 DE1751956A DE1751956A1 DE 1751956 A1 DE1751956 A1 DE 1751956A1 DE 19631751956 DE19631751956 DE 19631751956 DE 1751956 A DE1751956 A DE 1751956A DE 1751956 A1 DE1751956 A1 DE 1751956A1
Authority
DE
Germany
Prior art keywords
pressure
valve member
control
valve
seat
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
DE19631751956
Other languages
German (de)
Other versions
DE1751956C3 (en
DE1751956B2 (en
Inventor
Wilson Alexander John
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Girling Ltd
Original Assignee
Girling Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Girling Ltd filed Critical Girling Ltd
Publication of DE1751956A1 publication Critical patent/DE1751956A1/en
Publication of DE1751956B2 publication Critical patent/DE1751956B2/en
Application granted granted Critical
Publication of DE1751956C3 publication Critical patent/DE1751956C3/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
    • B60T8/36—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition including a pilot valve responding to an electromagnetic force
    • B60T8/3615—Electromagnetic valves specially adapted for anti-lock brake and traction control systems
    • B60T8/362—Electromagnetic valves specially adapted for anti-lock brake and traction control systems in pneumatic systems
    • B60T8/3625—Electromagnetic valves specially adapted for anti-lock brake and traction control systems in pneumatic systems having at least one vacuum connection
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
    • B60T13/241—Differential pressure systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
    • B60T8/44—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition co-operating with a power-assist booster means associated with a master cylinder for controlling the release and reapplication of brake pressure through an interaction with the power assist device, i.e. open systems
    • B60T8/447—Reducing the boost of the power-assist booster means to reduce brake pressure
    • B60T8/448—Reducing the boost of the power-assist booster means to reduce brake pressure the power-assist booster means being a vacuum or compressed air booster
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/72—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration responsive to a difference between a speed condition, e.g. deceleration, and a fixed reference
    • B60T8/74—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration responsive to a difference between a speed condition, e.g. deceleration, and a fixed reference sensing a rate of change of velocity

Description

Die Erfindung bezieht sich auf ein Steuerventil zum Steuern des Druckverhältnisses zwischen an den in zwei Kammern eines hydraulischen Zylinders oder dgl. herrschenden Drücken eines Druckmittels.The invention relates to a control valve for controlling the pressure ratio between the pressures of a pressure medium prevailing in two chambers of a hydraulic cylinder or the like.

Gemäß der Erfindung ist bei einem Drucksteuerventil der genannten Art ein in einem Gehäuse mittels einem inneren und einem äußeren bewegbaren Steuerglied schwimmend gelagertes und gegen eine Stirnwand des Gehäuses vorgespanntes erstes Ventilglied, ein gegen einen Sitz des Gehäuses vorgespanntes zweites Ventilglied und eine Verbindung zwischen zwei Räumen, von denen der erste zwischen den Steuergliedern eingeschlossen ist und mit der ersten Kammer in Verbindung steht und der zweite zwischen dem inneren Steuerglied und dem Sitz gebildet ist und mit der zweiten Kammer in Verbindung steht, wobei durch betätigen des ersten Ventilglieds zunächst die Verbindung unterbrechbar und dann das zweite Ventilglied vom seinem Sitz abhebbar ist, so daß Druckmittel anderen Druckes in dem zweiten Raum strömen kann, vorgesehen.According to the invention, in a pressure control valve of the type mentioned, there is a first valve member which is floatingly mounted in a housing by means of an inner and an outer movable control member and is pretensioned against an end wall of the housing, a second valve element pretensioned against a seat of the housing and a connection between two spaces, of which the first is enclosed between the control members and communicates with the first chamber and the The second is formed between the inner control member and the seat and is in communication with the second chamber, whereby the connection can be interrupted by actuating the first valve member and then the second valve member can be lifted from its seat so that pressure medium with a different pressure flows into the second chamber can, provided.

Die Erfindung wird im folgenden anhand schematischer Zeichnungen eines Ausführungsbeipiels näher erläutert.The invention is explained in more detail below with reference to schematic drawings of an exemplary embodiment.

Die Fig. 1 und 2 zeigen im Schnitt einen Hilfszylinder mit einem daran angeschlossenen Drucksteuerventil in unbetätigter und in betätigter Stellung.1 and 2 show in section an auxiliary cylinder with a pressure control valve connected to it in the non-actuated and in the actuated position.

Der Hilfszylinder nach Fig. 1 und 2 umfaßt einen Druckzylinder 44 und einem darin spielenden Kolben 62. Die eine Kammer des Zylinders 47 ist durch eine Leitung 45 mit einer Unterdruckquelle verbunden. Beide Kammern des Zylinders sind über je eine Leitung 46 und 47 an das Gehäuse 48 des Drucksteuerventiles angeschlossen. Ein Ende des Gehäuses 48 ist über Öffnungen 49 mit der Atmosphäre verbunden, während das andere von einer Stirnwand gebildete Ende einen Kanal 51 für die Zufuhr von Steuerluft aufweist, die z.B. von einer bekannten Antiblockiereinrichtung für die Bremsen von Kraftfahrzeugen geliefert wird. Ein Ventilteller 52 ist durch eine Feder 53 gegen einen ringförmigen Sitz 54 des Gehäuses 48 vorgespannt, so daß er normalerweise die Verbindung zwischen der Leitung 46 und derThe auxiliary cylinder according to FIGS. 1 and 2 comprises a pressure cylinder 44 and a piston 62 playing therein. One chamber of the cylinder 47 is connected by a line 45 to a vacuum source. Both chambers of the cylinder are connected to the housing 48 of the pressure control valve via a line 46 and 47 each. One end of the housing 48 is connected to the atmosphere via openings 49, while the other end, formed by an end wall, has a channel 51 for the supply of control air, which is supplied, for example, by a known anti-lock device for the brakes of motor vehicles. A valve disk 52 is biased by a spring 53 against an annular seat 54 of the housing 48, so that it normally the connection between the line 46 and the

Atmosphäre verschlossen hält. Im Gehäuse 48 ist ein becherförmiges Ventilglied 55 mittels zweier in einem Abstand voneinander angeordneter Membranen 56 und 57 schwimmend aufgehängt. Die Leitung 47 ist mit dem Raum zwischen diesen Membranen verbunden. Eine Bohrung 58 im Boden des Bechers 55 verbindet den Raum zwischen den Membranen 56 und 57 mit dem Raum zwischen der äußeren Membran 57 und der Stirnwand des Gehäuses 48. Der Becher 55 wird von einer Feder 59 normalerweise in der in Fig. 1 gezeigten Stellung gehalten, in der er sich in einem Abstand von dem Tellerventil 52 befindet. In der Wand des Bechers 55 ist im Bereich zwischen den Membranen 56 und 57 eine Bohrung 61 vorgesehen, so daß die Leitungen 46 und 47 bei der Stellung des Bechers 55, 54 noch Fig. 1 miteinander in Verbindung stehen und in beiden Kammern des Zylinders 44 Unterdruck herrscht.Keeps the atmosphere closed. A cup-shaped valve member 55 is suspended in a floating manner in the housing 48 by means of two membranes 56 and 57 arranged at a distance from one another. The line 47 is connected to the space between these membranes. A bore 58 in the bottom of the cup 55 connects the space between the diaphragms 56 and 57 with the space between the outer diaphragm 57 and the end wall of the housing 48. The cup 55 is normally held in the position shown in FIG. 1 by a spring 59 in which it is at a distance from the poppet valve 52. In the wall of the cup 55, a bore 61 is provided in the area between the membranes 56 and 57 so that the lines 46 and 47 are still in connection with one another in the position of the cup 55, 54 and in both chambers of the cylinder 44 There is negative pressure.

Wenn dem Drucksteuerventil über den Kanal 51 Steuerluft zugeführt wird, bewegt sich der Becher 55 nach links und greift am Boden des Ventiltellers an, um zuerst die Verbindung zwischen der Leitung 46 und der Unterdruckquelle zu unterbrechen und dann dem Ventilteller 52 von seinem Sitz abzuheben, so daß die Leitung 46 mit der Atmosphäre verbunden wird. Jetzt tritt Luft unter Atmosphärendruck in die linke Kammer des Zylinders 44 ein, so daß der Kolben 62 nach rechts bewegt wird.When control air is supplied to the pressure control valve via the channel 51, the cup 55 moves to the left and engages the bottom of the valve disk to first interrupt the connection between the line 46 and the vacuum source and then to lift the valve disk 52 from its seat, see above that the line 46 is connected to the atmosphere. Now air under atmospheric pressure enters the left chamber of the cylinder 44 so that the piston 62 is moved to the right.

Verwendet man das beschriebene Ventil in Verbindung mit einer Antiblockiereinrichtung zum Verhindern des Blockierens gebremster Räder eines Kraftfahrzeuges, so kann die Steuerluftzufuhr zu dem Drucksteuerventil zunächst derart verringert werden, daß der Ventilteller 52 zwar zur Anlage an seinem Sitz kommt, um die Zufuhr von Luft unter Atmosphärendruck zum Zylinder 44 zu unterbrechen, das andere Ventilorgan 55 jedoch in Anlage an dem Ventilteller 52 bleibt, so daß der Kolben 62 des Zylinders 44 erst zurückkehrt, wenn die Steuerluftzufuhr vollständig eingestellt wird.If the valve described is used in conjunction with an anti-lock device to prevent the braked wheels of a motor vehicle from locking, the control air supply to the pressure control valve can initially be reduced in such a way that the valve disk 52 comes to rest on its seat to allow the supply of air under atmospheric pressure to interrupt the cylinder 44, but the other valve member 55 remains in contact with the valve disk 52, so that the piston 62 of the cylinder 44 does not return until the control air supply is completely stopped.

Der Kolben 62 kann direkt auf das Bremspedal 63 eines Kraftfahrzeugs wirken, um es in Richtung auf seine Ruhestellung zu bewegen, wie es in Fig. 1 und 2 gezeigt ist. Er kann aber auch auf den Kolben eines Hauptbremszylinders wirken, oder er kann lediglich das Volumen eines Teils einer hydraulischen Übertragungsleitung zwischen dem Hauptzylinder und dem Radzylindern einer Kraftfahrzeugbremse vergrößern.The piston 62 can act directly on the brake pedal 63 of a motor vehicle in order to move it towards its rest position, as is shown in FIGS. 1 and 2. However, it can also act on the piston of a master brake cylinder, or it can only increase the volume of part of a hydraulic transmission line between the master cylinder and the wheel cylinders of a motor vehicle brake.

Bei einer alternativen Anordnung kann das Drucksteuerventil mit einem vakuumbetätigten Kraftverstärker verbunden sein, über den ein hydraulischer Hauptzylinder betätigbar ist. Das Drucksteuerventil steuert bei diesem Anwendungsfall den Druckunterschied im Kraftverstärker.In an alternative arrangement, the pressure control valve can be connected to a vacuum-actuated power booster, via which a hydraulic master cylinder can be actuated. In this application, the pressure control valve controls the pressure difference in the booster.

Claims (6)

1. Drucksteuerventil zum Steuern des Druckverhältnisses zwischen den in zwei Kammern eines hydraulischen Zylinders oder dgl. herrschenden Drücken eines Druckmittels, gekennzeichnet durch ein in einem Gehäuse (48) mittels einem inneren und einem äußeren bewegbaren Steuerglied (56 und 57) schwimmend gelagertes und gegen eine Stirnwand des Gehäuses vorgespanntes erstes Ventilglied (55), ein gegen einen Sitz (54) des Gehäuses (48) vorgespanntes zweites Ventilglied (52) und eine Verbindung (61) zwischen zwei Räumen, von denen der erste zwischen den Steuergliedern (56, 57) eingeschlossen ist und mit der ersten Kammer in Verbindung steht und der zweite zwischen dem inneren Steuerglied (56) und dem Sitz (54) gebildet ist und mit der zweiten Kammer in Verbindung steht, wobei durch Betätigen des ersten Ventilglieds (55) zunächst die Verbindung (61) unterbrechbar und dann das zweite Ventilglied (52) von seinem Sitz abhebbar ist, so daß Druckmittel anderen Druckes in den zweiten Raum strömen kann.1. Pressure control valve for controlling the pressure ratio between the pressures of a pressure medium in two chambers of a hydraulic cylinder or the like End wall of the housing biased first valve member (55), a second valve member (52) biased against a seat (54) of the housing (48) and a connection (61) between two spaces, the first of which between the control members (56, 57) is enclosed and is in communication with the first chamber and the second is formed between the inner control member (56) and the seat (54) and is in communication with the second chamber, wherein by actuating the first valve member (55) first the connection ( 61) can be interrupted and then the second valve member (52) can be lifted from its seat so that pressure medium with a different pressure can flow into the second space. 2. Drucksteuerventil nach Anspruch 1, dadurch gekennzeichnet, daß das erste Ventilglied (55) durch einen Steuerdruck betätigbar ist, der dem von dem äußeren bewegbaren Steuerglied (57) und der Stirnfläche des Ventilgliedes (55) einerseits und der Innenseite der Stirnwand des Gehäuses (48) andererseits begrenzten Steuerdruckraum zuführbar ist.2. Pressure control valve according to claim 1, characterized in that the first valve member (55) can be actuated by a control pressure which can be fed to the control pressure chamber delimited by the outer movable control element (57) and the end face of the valve element (55) on the one hand and the inside of the end wall of the housing (48) on the other hand. 3. Drucksteuerventil nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß das erste Ventilglied von einem zum zweiten Ventilglied (52) hin offenen Becher (55) gebildet ist, dass die Verbindung von einer im Bereich zwischen den beiden bewegbaren Steuergliedern (56, 57) vorgesehenen Querbohrung (61) durch die Wand des Bechers (55) hergestellt ist und daß der Becher (55) bei seiner Betätigung mit dem Boden des tellerförmig ausgebildeten zweiten Ventilgliedes (52) zusammenwirkt, um die Verbindung (61) zu unterbrechen und das zweite Ventilglied (52) von seinem Sitz (54) abzuheben.3. Pressure control valve according to claim 1 or 2, characterized in that the first valve member is formed by a cup (55) open towards the second valve member (52), that the connection of one in the area between the two movable control members (56, 57) provided transverse bore (61) is made through the wall of the cup (55) and that the cup (55) cooperates with its actuation with the bottom of the plate-shaped second valve member (52) to interrupt the connection (61) and the second valve member (52) to be lifted from its seat (54). 4. Drucksteuerventil nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß in dem Boden das das erste Ventilglied bildenden Bechers (55) eine Verbindungsbohrung (58) zum Steuerdruckraum vorgesehen ist.4. Pressure control valve according to one of claims 1 to 3, characterized in that a connecting bore (58) to the control pressure chamber is provided in the bottom of the cup (55) forming the first valve member. 5. Drucksteuerventil nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß das erste und das zweite Ventilglied (55 und 52) durch je eine Feder (53 bzw. 59) gegen die Stirnwand des Gehäuses (48) bzw. dem Sitz (54) vorgespannt sind.5. Pressure control valve according to one of claims 1 to 4, characterized in that the first and the second valve member (55 and 52) each by a spring (53 or 59) against the end wall of the housing (48) or the seat (54 ) are preloaded. 6. Drucksteuerventil nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die bewegbaren Steuerglieder Membranen (56, 57) umfassen.6. Pressure control valve according to one of claims 1 to 5, characterized in that the movable control members comprise membranes (56, 57).
DE19631751956 1962-09-27 1963-09-26 Control valve for a braking force control system of a vehicle Expired DE1751956C3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB3667262A GB1042772A (en) 1962-09-27 1962-09-27 Anti-skid device for vehicles
GB3667262 1962-09-27

Publications (3)

Publication Number Publication Date
DE1751956A1 true DE1751956A1 (en) 1972-03-09
DE1751956B2 DE1751956B2 (en) 1975-06-05
DE1751956C3 DE1751956C3 (en) 1976-01-29

Family

ID=

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992020556A1 (en) * 1991-05-15 1992-11-26 Lucas Industries Public Limited Company Vehicle braking system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992020556A1 (en) * 1991-05-15 1992-11-26 Lucas Industries Public Limited Company Vehicle braking system
GB2271822A (en) * 1991-05-15 1994-04-27 Lucas Ind Plc Vehicle braking system

Also Published As

Publication number Publication date
GB1042773A (en) 1966-09-14
GB1042772A (en) 1966-09-14
DE1751956B2 (en) 1975-06-05

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Legal Events

Date Code Title Description
C3 Grant after two publication steps (3rd publication)
E77 Valid patent as to the heymanns-index 1977
EHJ Ceased/non-payment of the annual fee