DE102019113445A1 - Control valve for a hydraulic actuator system, an operating method for an actuator system, and an adjustment method for a control valve - Google Patents

Abstract

The invention relates to a control valve (1) with a valve axis (14) for a hydraulic actuator system (2), having at least the following components: a valve body (3) with a first valve outlet (4), with a second valve outlet (8) and with a valve inlet (12), the valve inlet (12) having a control opening (13); and - a valve slide (15) which is actively movable along the valve axis (14) and has a first slide element (6) and a second slide element (10), the first valve outlet (4) having a first seat system (7) and the second valve outlet (8) ) comprises a second seat system (11), and wherein the first slide element (6) forms a first seat contact pairing (5) with the first seat system (7) and the second slide element (10) forms a second seat contact pair (9) with the second seat system (11) , wherein the valve slide (15) is set up to close and open the seat contact pairings (5,9) and to control the valve inlet (12). The control valve is primarily characterized in that the first pair of seat contacts (5) can be axially displaced relative to the second pair of seat contacts (9). The invention also relates to an operating method for an actuator system and an adjustment method for a control valve. With the control valve and operating method proposed here, as well as the adjustment method, efficient operation of an actuation unit is made possible in a small installation space at low cost.

Description

The invention relates to a control valve for a hydraulic actuator system and an actuator system with such a control valve for an actuating unit of a friction clutch, furthermore an operating method for such an actuator system, and an adjustment method for such a control valve.

Control valves are known from the prior art in which a pressure build-up in an actuating unit of an actuator system can be controlled, for example by means of a control edge on a valve inlet which is connected to a hydraulic supply device, for example a volume flow source, for example a pressure circuit of a motor hydraulics of an internal combustion engine, or a pressure source , for example a pump, is connected. If a desired operating pressure is set, the operating pressure is either maintained by means of the hydraulic supply device, i.e. the valve inlet is kept open, or by means of an additional pressure valve between the control valve and the actuating unit, while the connection to the control valve is disconnected. In the latter case, the pressure in the hydraulic supply device or at the valve inlet can be reduced. However, additional installation space and an additional control architecture are required.

Proceeding from this, the present invention is based on the object of at least partially overcoming the disadvantages known from the prior art. The features according to the invention emerge from the independent claims, for which advantageous configurations are shown in the dependent claims. The features of the claims can be combined in any technically meaningful manner, with the explanations from the following description as well as features from the figures, which include supplementary embodiments of the invention, can also be used.

• - einen Ventilkörper mit einem ersten Ventilauslass, mit einem zweiten Ventilauslass und mit einem Ventileinlauf, wobei der Ventileinlauf eine Steueröffnung aufweist; und
• - einen entlang der Ventilachse aktiv bewegbaren Ventilschieber mit einem ersten Schieberelement und mit einem zweiten Schieberelement,

wobei der erste Ventilauslass eine erste Sitzanlage und der zweite Ventilauslass eine zweite Sitzanlage umfasst, und
wobei das erste Schieberelement mit der ersten Sitzanlage eine erste Sitzkontaktpaarung und das zweite Schieberelement mit der zweiten Sitzanlage eine zweite Sitzkontaktpaarung bildet,
wobei der Ventilschieber zum Schließen und Öffnen der Sitzkontaktpaarungen und zum Steuern des Ventileinlaufs eingerichtet ist.The invention relates to a control valve with a valve axis for a hydraulic actuator system, having at least the following components:

• a valve body with a first valve outlet, with a second valve outlet and with a valve inlet, the valve inlet having a control opening; and
• - a valve slide actively movable along the valve axis with a first slide element and with a second slide element,

wherein the first valve outlet comprises a first seat system and the second valve outlet comprises a second seat system, and
wherein the first slide element forms a first seat contact pairing with the first seat system and the second slide element forms a second seat contact pairing with the second seat system,
wherein the valve slide is set up to close and open the seat contact pairings and to control the valve inlet.

The control valve is primarily characterized in that the first pair of seat contacts is axially displaceable relative to the second pair of seat contacts.

In the following, reference will be made to the valve axis mentioned if the axial direction and corresponding terms are used without explicitly otherwise indicating. Unless explicitly stated otherwise, ordinal numbers used in the preceding and following description are only used for clear distinction and do not reflect any order or ranking of the components identified. An ordinal number greater than one does not necessarily mean that another such component must be present.

The control valve is set up for a hydraulic actuator system, for example an actuation unit for a friction clutch or for a gearbox. Two main states are to be set, namely to put the actuator system without pressure (for example atmospheric pressure) and to set one or more different operating pressures.

The control valve includes a valve body, also referred to as a housing, which forms the necessary openings and a displacement, and a valve slide, which is axially movable in the displacement of the valve body, i.e. along a valve axis, by means of an actuator and preferably for an opposite direction by means of an energy storage element that is antagonistic to the direction of actuation of the actuator. In one embodiment, the actuator is set up to open and the antagonistic energy storage element is set up to close. For most applications, the actuator is designed to close and the antagonistic energy storage element to open, because then the least (electrical) energy is consumed in the main operating state of the control valve, which is present for the largest part of the time. The valve body preferably forms the guide track for the valve slide and thus defines the valve axis. For example, only the displacement with its wall forms such a guide path with at least one of the slide elements.

In a preferred embodiment with a high energy efficiency, for setting or maintaining an atmospheric Pressure (pressureless position) or vice versa, no control energy is required for setting or maintaining an operating pressure. For example, the valve slide is moved axially into an (energy-consuming) working position by means of an actuator and held there and is pretensioned by means of an antagonistic energy storage element, for example a helical spring, in such a way that the valve slide is moved back into the opposite (energy-free) rest position and held there . Such an actuator includes, for example, a magnet armature, for example with a solenoid piston, or a self-locking spindle drive.

The openings of the valve body form a first valve outlet and a second valve outlet, as well as a valve inlet. Each of the openings is, for example, a single or a plurality of passages in the valve body. Towards the valve slide, these openings form a first seat system (at the first valve outlet), a second seat system (at the second valve outlet) and a control opening (at the valve inlet). The control opening preferably cooperates with a control edge (for example a cylindrical section) of the valve slide. The valve inlet is preferably set up in such a way that a volume inflow or a pressure increase (for example with a constant pressure applied) at the valve inlet can be set by means of a (changeable) axial position of the control edge. The openings of the valve body are preferably only designed for opening and closing and do not have an outlet control edge. Alternatively, an outlet control edge for controlling the volume inflow or the pressure increase is provided on at least one of the openings, with a (second) outlet control edge at the second valve outlet preferably not being able to control the valve inlet and no control edge being provided. The valve inlet can then be controlled indirectly by the valve slide by controlling the pressure change at the second seat system.

The first valve outlet is to be connected to an (overflow) tank when in use, so that if the pressure in the actuator system is reduced, the hydraulic fluid can flow out into the tank via the first valve outlet. The tank is depressurized. The other (i.e. the second) of the two valve outlets is to be connected to the actuator system during use, for example a slave piston. When the valve inlet is open (and the first valve outlet is closed), the actuator system is then supplied with the set pressure via the second valve outlet. If both valve outlets are open, the pressure is reduced accordingly. For a quick reaction (quick drainage behavior) and / or low energy consumption, the valve inlet is preferably completely closed during this pressure reduction.

The respective seat contact pairing is formed by a slide element and a corresponding seat system. The slide element can be pressed against the corresponding seat system, so that a flow through the associated valve outlet is interrupted, that is to say no pressure equalization takes place, preferably a negligible leakage occurs at most. For example, the respective slide element is designed with an inclined, for example conical, contact surface in the case of a cylindrical cubic capacity, and the seat system with an edge (seat edge) for linear contact with the respective contact surface. This is advantageous for fast running behavior. Alternatively, the structure is reversed, that is, the seat system forms an inclined contact surface and the slide element forms an edge.

It is now proposed that the slide elements and the control edge of the control opening can be actuated by a common valve slide and thus by means of a single common actuator, in that the first seat contact pairing is relatively displaceable to the second seat contact pairing. The relative displaceability is created by means of a movability of at least one of the slide elements relative to the valve slide and / or at least one seat system relative to the valve body. The slide elements can therefore be moved axially by means of the valve slide and thus perform the lifting movement with the valve slide. In the case of a slide element which is axially movable relative to the valve slide, the stroke movement is superimposed on this relative mobility. The seat systems are part of the (rigid) valve body and therefore do not perform any lifting movement. In a corresponding embodiment, the seating systems are not rigid, but rather can be moved relatively.

The control valve proposed here can thus be operated in such a way that the first valve outlet can be kept closed in a first pressure build-up position, while the second valve outlet and the valve inlet are open. The valve inlet is preferably controllable by means of the axial movement of the valve slide, that is to say the control edge. If the set pressure is to be maintained in the second valve outlet, the first valve outlet is overpressed, that is, a relative movement is caused in the first seat contact pairing, and the second valve outlet is closed. The valve inlet is preferably closed so that the (source) pressure can be switched off at the valve inlet and / or the axial force component on the valve slide resulting from the pressure in the displacement can be reduced. If the pressure can be adjusted with a control edge of the valve slide, the pressure rises briefly when the second valve outlet closes because the control opening is opened further. This is not a problem for most applications, for example because of the desired operating pressure corresponds to a minimum required pressure and a higher pressure for the actuator system in this operating state is harmless. And if the pressure is to be reduced again, the first valve outlet and the second valve outlet are opened and the pressure is reduced as described above.

A pressure can thus be maintained with a single control valve, with energy-efficient operation being possible.

It is also proposed in an advantageous embodiment of the control valve that the first seat assembly is axially fixed and the first slide element is axially displaceable relative to the valve slide, and preferably the second seat assembly is axially fixed and the second slide element relative to the valve slide is axially fixed.

In this embodiment, for example, the first slide element is set up as a cylinder, for example as a sleeve, with a central through opening for the valve slide. The valve slide extends through the first slide element to the second slide element and to a closing element, for example a cylindrical section of the valve slide, preferably with a control edge, for the valve inlet. The first slide element is supported in an axially pretensioned manner on a stop of the valve slide by means of a (first) energy storage element, for example a helical compression spring. The first valve outlet can thus be closed (by means of the pretensioning force) while the second valve outlet is still open. To close the second valve outlet, the position of the first slide element is overpressed, that is, an axial overstroke is carried out, with only the energy storage element storing greater energy and, for example, the first slide element being pressed more strongly into the first seat system.

In a simple embodiment, the second slide element is axially fixed to the valve slide and the second seat system is axially fixed to the valve body. The relative movement between the valve slide and valve body thus corresponds to the control position of the second slide element or the open position of the second seat contact pairing. Particularly preferably, the closing element for the valve inlet is also axially fixed to the valve slide. A double fit is harmless here because they are actuated axially opposite one another. In the open state of the second pair of seat contacts, the volume flow or the pressure at the valve inlet is controlled, for example by means of a control edge. When the control opening of the valve inlet is controlled directly, the second pair of seat contacts is open enough not to influence the control or the influence is known (for example empirically). In the closed state of the second pair of seat contacts, the degree of the open position of the valve inlet is not relevant.

It is further proposed in an advantageous embodiment of the control valve that the first slide element is axially fixed relative to the valve slide and the first seat system is axially displaceable relative to the valve body, the second slide element preferably being axially fixed relative to the valve slide and the second seat system is axially displaceable relative to the valve body.

In this embodiment, the first slide element is axially fixed to the valve slide. The valve slide is also connected to the second slide element and to the closing element, preferably with a control edge, for the valve inlet. The first seat system is supported in an axially pretensioned manner against a stop of the valve body by means of a (first) energy storage element, for example a disk spring package. The first valve outlet can thus be closed (by means of the pretensioning force) while the second valve outlet is still open. To close the second valve outlet, the position of the first slide element is overpressed, that is, an axial overstroke is carried out, with only the energy storage element storing greater energy and, for example, the first slide element being pressed more strongly into the first seat system.

In a simple embodiment, the second slide element is axially fixed to the valve slide and the second seat system is axially fixed to the valve body. The relative movement between the valve slide and valve body thus corresponds to the control position of the second slide element or the open position of the second seat contact pairing. Particularly preferably, the closing element for the valve inlet is also axially fixed to the valve slide. A double fit is harmless here because they are actuated axially opposite one another. For an explanation, reference is made to the embodiment described above.

In another embodiment, the second slide element is axially fixed with the valve slide, but the second seat system is not axially fixed with the valve body, but axially displaceable. The relative movement between the second seat system and the valve body enables a fine adjustment of the closed position of the second slide element, preferably even an automatic readjustment during operation when wear occurs, for example abrasion. The second seat contact pairing is very particularly preferably axially relative to the one controlled by means of the control edge Finely adjustable valve inlet. For the rest, the description of the embodiment described immediately above with the axially fixed second seat contact pairing applies to this embodiment.

It is further proposed in an advantageous embodiment of the control valve that the second slide element is designed to open and close the valve inlet and to open and close the second valve outlet, a first bypass channel connecting the open valve inlet and the opened second valve outlet, and
that the first slide element is set up to open and close a second bypass channel, the second bypass channel connecting the opened first valve outlet and the opened second valve outlet,
wherein the first valve outlet and the second valve outlet are preferably connected by means of the first bypass channel when the valve inlet is closed,
and particularly preferably the first slide element permanently forms a gap seal with respect to the second bypass channel.

This embodiment is particularly advantageous in order to decouple the pressure conditions, that is to say the actuator forces and antagonist forces, from the required volume flows. If, for example, an actuating cylinder of a friction clutch is to be controlled by means of this control valve, the cross-sections of the bypass channels that can be flowed through can be adapted for different actuation path lengths and / or actuation speeds without the actuator and / or an energy storage element having to be adapted or even replaced.

The second slide element is aligned here with its second contact surface facing away from the closing element of the valve inlet, so that a first bypass channel leads past the second slide element, that is to say bridges it. In one embodiment, the closing element and the second contact surface are axially fixed on a common element, for example a cylindrical shoulder of the valve slide, on the valve slide. The first slide element is arranged axially behind the second slide element in the direction of the second contact surface. If the first slide element is axially displaceable relative to the valve slide, then the first slide element is preferably supported on the second slide element in an axially prestressed manner by means of a first energy storage element. In the case of an axially displaceable first seat system, this is supported on the valve body in an axially pretensioned manner. In a simple embodiment, the first slide element is axially fixed relative to the valve slide and relative to the second slide element.

The second bypass channel is set up as a relief channel, so that it is ensured that the valve slide does not have to work against an enclosed liquid reservoir. In one embodiment, the second bypass channel is also set up as a drain connection between the second valve outlet and the first valve outlet. If the second bypass channel is set up exclusively as a relief channel, a gap seal is permanently formed with the second bypass channel, for example by means of a cylinder extension in the direction of the first contact surface behind the first slide element, for example as a shoulder on the valve slide.

In a preferred embodiment, a direct outlet connection is formed between the second valve outlet and the first valve outlet by means of the first bypass channel when the valve inlet is closed. A closing slide at the first valve outlet, which closes the first valve outlet when the valve inlet is open, is displaced so far in the closed position of the valve inlet that the first valve outlet is opened. The second valve outlet is then open at the same time. The first bypass channel then connects the first valve outlet and the second valve outlet, specifically directly, the second slide element being bridged.

In one embodiment, the first pair of seat contacts and / or the second pair of seat contacts can be finely adjusted, preferably by means of a respective seat system that is axially displaceable relative to the valve body.

It is also proposed in an advantageous embodiment of the control valve that the seat system of the axially displaceable seat contact pairing is designed to be axially softer than the corresponding slide element and that the seat system is made with an axial oversize so that the seat system of the corresponding slide element is at least first closed the corresponding valve outlet is permanently axially displaced,
wherein the seat system is preferably made axially softer than the corresponding slide element by means of a spring element,
and particularly preferably the spring element is mechanically fixed in a displaced state.

In this embodiment, an automatic fine adjustment by means of mechanical softness of the seat contact pairing concerned is made possible. For example, a material pairing of the contact surface and the corresponding seat system is set in such a way that one of the two surfaces deforms the other plastically with a corresponding adjustment pressure or elastically with an operating pressure. Suitable as For example, a softer material is aluminum (for plastic deformation) with steel as the harder material. In the case of a purely elastic deformation, a rubber-elastic material is suitable, for example. In a preferred embodiment, the (axial) softness is formed by means of a spring element. In a particularly preferred embodiment, such a spring element is mechanically fixed after a displacement, for example as a plate spring (package), which digs radially into the valve body during compression or is canted with the valve body. In one embodiment, the mechanical fixation is only so slight that it can be released under a permissible external load, for example a vibration load. The fine adjustment is then carried out automatically again with the next valve stroke.

• - ein Steuerventil nach einem der vorhergehenden Ansprüche;
• - eine hydraulische Versorgungseinrichtung, welche mit dem Ventileinlauf verbunden ist;
• - einen Tankanschluss, welcher mit dem ersten Ventilauslass verbunden ist;
• - einen Betätigungsanschluss, welcher mit dem zweiten Ventilauslass verbunden ist,

wobei bei in dem Betätigungsanschluss aufgebautem Betriebsdruck der erste Ventilauslass und der zweite Ventilauslass mittels des Ventilschiebers zugleich verschließbar sind.According to a further aspect, an actuator system for an actuation unit of a friction clutch is proposed, having at least the following components:

• - A control valve according to one of the preceding claims;
• - A hydraulic supply device which is connected to the valve inlet;
• a tank connection which is connected to the first valve outlet;
• - an actuation connection which is connected to the second valve outlet,

With the operating pressure built up in the actuation connection, the first valve outlet and the second valve outlet can be closed at the same time by means of the valve slide.

The actuator system is set up for an actuation unit of a friction clutch, but can also be used, for example, for a switchable translation or a braking device. If the control valve is to be used in a particularly energy-saving manner, the relieved state, i.e. when the connection between the first valve outlet and the second valve outlet is open, is the main state, while this main state is maintained by an energy storage element that is antagonistic to an active actuator for operating the valve slide. The control valve sits between a hydraulic supply device, an actuation connection and a tank connection for controlling purposes. The hydraulic supply device is an active pump or a (for example, approximately constant pressure) pressure circuit, for example for the engine control of an internal combustion engine. The tank connection is preferably made pressure-free and connected to an overflow tank, which is preferably set up to return hydraulic fluid to the hydraulic supply device. At least such a low pressure is applied to the tank connection that the actuation unit can be completely relieved, namely passively, that is to say without pumping power. The actuation connection connects the second valve outlet to an actuation unit, for example a slave cylinder.

The control valve now enables the operating pressure at the actuation connection to be maintained without additional functional units, for example a closing valve, and the pressure of the hydraulic supply device is not required for this, for example a pump can be switched off or the power at the pump of a pressure circuit can be reduced.

1. i. an dem Ventileinlauf Bereitstellen eines Versorgungsdrucks der hydraulischen Versorgungseinrichtung;
2. ii. Öffnen oder Offenhalten des Ventileinlaufs, Öffnen oder Offenhalten des zweiten Ventilauslasses und mittels einer erhöhten Stellkraft an dem Ventilschieber Schließen oder Geschlossenhalten des ersten Ventilauslasses;
3. iii. Aufbauen eines Drucks in dem Betätigungsanschluss bis Erreichen eines Betriebsdrucks;
4. iv. mittels einer weiter erhöhten Stellkraft an dem Ventilschieber Schließen des Ventileinlaufs, Schließen des zweiten Ventilauslasses und Geschlossenhalten des ersten Ventilauslasses; und
5. v. wenn ein Abbau des Betriebsdrucks in dem Betätigungsanschluss gewünscht ist, Öffnen des ersten Ventilauslasses und des zweiten Ventilauslasses.

According to a further aspect, an operating method for an actuator system according to an embodiment according to the above description is proposed, the operating method comprising the following steps in the order mentioned:

1. i. providing a supply pressure of the hydraulic supply device at the valve inlet;
2. ii. Opening or keeping open the valve inlet, opening or keeping open the second valve outlet and, by means of an increased actuating force on the valve slide, closing or keeping closed the first valve outlet;
3. iii. Building up a pressure in the actuating connection until an operating pressure is reached;
4. iv. by means of a further increased actuating force on the valve slide, closing the valve inlet, closing the second valve outlet and keeping the first valve outlet closed; and
5. v. when a reduction in the operating pressure in the actuation port is desired, opening the first valve outlet and the second valve outlet.

Said operating method can be implemented in order to build up a, preferably high, operating pressure by means of the control valve described above, integrated into the actuator system described above. The regular sequence is described here, in which a desired operating pressure is first built up at the actuation connection and then (at any later point in time) the operating pressure is completely reduced again. Such a regular sequence can of course also be interrupted, for example a reduction in pressure as in step v. can be initiated before the desired operating pressure is reached. Also, a pressure at the actuation connection does not have to be completely reduced before a desired operating pressure is built up again. It should also be noted that different operating pressures are adjustable, for example for different required operating positions and / or operating forces of an operating unit. For example, when the pressure at the valve inlet is reduced, a friction clutch can be fixed in an intermediate position (for example slipping torque transmission) in that the second valve outlet is closed and a reduced operating pressure is maintained.

It should be pointed out that process aspects, as they are explained in connection with the control valve and the actuator system in the remainder of the description, are at least an optional component of the operating process shown. It should also be noted that in an embodiment with an actuator acting in both directions for actuating the valve slide, an increase in the actuating force can be almost negligible and affects the counter-pressure effect of the hydraulic fluid on the slide elements and the opposing over-travel force at the first valve outlet limited. In the case of an actuator which works together with an energy storage element which acts in an antagonistic manner, the actuating force for carrying out step ii. and step iv. largely defined by the spring characteristic of the energy storage element, for example if a fast passive reaction (fast running behavior) of the control valve is desired. In an embodiment with the closed position in the passive state, the increase in the actuating force is the difference between the (then decreasing) active actuator force and the (mostly also decreasing, but less strongly decreasing) passive storage force.

• Verringern des Versorgungsdrucks der hydraulischen Versorgungseinrichtung an dem Ventileinlauf,

wobei bevorzugt anschließend die Stellkraft an dem Ventilschieber verringert wird.It is also proposed in an advantageous embodiment of the operating method that a step vi. after step iv. includes:

• Reducing the supply pressure of the hydraulic supply device at the valve inlet,

wherein the actuating force on the valve slide is then preferably reduced.

Because in many applications the leakage in the hydraulic supply system or the pressure supply system on the control valve side can only be influenced to a small extent due to the required line lengths and line complexity, it is particularly advantageous if the pressure can be reduced or completely reduced there. This means that there is no need to maintain the operating pressure over the entire pressure supply system, and leakage losses do not have to be replenished. This also saves a considerable amount of energy on the hydraulic supply device. However, at the same time as the control valve, no additional control device that takes up installation space is necessary. Rather, all that needs to be applied is an actuator force to hold the valve slide in the fully closed position (according to step iv.). Alternatively, an active, i.e. energy-absorbing, actuator force must be applied to reduce the pressure, and an energy storage element acts passively when it is kept closed.

1. a. Einschieben des Ventilschiebers in den Ventilkörper;
2. b. axiales Andrücken des ersten Schieberelements gegen die korrespondierende erste Sitzanlage und/oder des zweiten Schieberelements gegen die korrespondierende zweite Sitzanlage mit einer Montagekraft;
3. c. während Schritt b., Erfassen der Dichtigkeit der ersten Sitzkontaktpaarung und/oder der zweiten Sitzkontaktpaarung; und
4. d. sobald eine ausreichende Dichtigkeit an der ersten Sitzkontaktpaarung und/oder der zweiten Sitzkontaktpaarung erreicht ist, Abbrechen des Schritts b..

According to a further aspect, an adjustment method for a control valve according to an embodiment according to the above description is proposed, the adjustment method comprising the following steps in the order mentioned:

1. a. Pushing the valve slide into the valve body;
2. b. axially pressing the first slide element against the corresponding first seat system and / or the second slide element against the corresponding second seat system with an assembly force;
3. c. during step b., detecting the tightness of the first seat contact pairing and / or the second seat contact pairing; and
4. d. as soon as sufficient tightness is achieved on the first seat contact pairing and / or the second seat contact pairing, step b is canceled.

The tightness is measured indirectly or directly in this adjustment process. Indirect detection is, for example, via detection of a change in volume or a change in pressure in a slave cylinder, the leakage of the connected system then having to be known or at least negligible. For example, the tightness is determined on a test stand with well-known boundary conditions. The mentioned adjustment method shows only one possible variant of adjustment or fine adjustment of a control valve according to the preceding description. This adjustment process has the advantage that it can be carried out blindly, i.e. solely based on measured pressure values or (leakage) volume flow measurements without additional insights into the control valve. In one embodiment, the adjustment process is repeated, for example during operation, if the tightness has become insufficient. The tightness is monitored at least indirectly during operation, for example by means of pressure monitoring in a slave cylinder and / or the position of a slave piston in an actuating unit. The assembly force, by means of which the tightness of the relevant seat contact pairing can be adjusted, is preferably significantly greater than the maximum required actuating force when the control valve is in operation, ie when the closed position is maintained. Alternatively, the amount of the assembly force also corresponds to the maximum required actuating force. Then An adjustment potentially takes place each time the second valve outlet is closed. The adjustment is, however, characterized in that there is an improvement in the tightness and / or an axial relative movement between the contact surface and the corresponding seat contact of the seat contact pairing.

• 1: Steuerventil in einer ersten Ausführungsform;
• 2: Steuerventil in einer zweiten Ausführungsform;
• 3: Steuerventil in einer dritten Ausführungsform;
• 4: Steuerventil in einer vierten Ausführungsform;
• 5: Aktorsystem mit Steuerventil;
• 6: Flussdiagramm eines Betriebsverfahrens des Aktorsystems; und
• 7: Flussdiagramm eines Justierverfahrens des Steuerventils.

The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way restricted by the purely schematic drawings, it being noted that the drawings are not dimensionally accurate and are not suitable for defining size relationships. It is shown in

• 1 : Control valve in a first embodiment;
• 2 : Control valve in a second embodiment;
• 3 : Control valve in a third embodiment;
• 4th : Control valve in a fourth embodiment;
• 5 : Actuator system with control valve;
• 6 : Flow diagram of an operating method of the actuator system; and
• 7th : Flow chart of an adjustment process of the control valve.

In 1 is a functional diagram of a control valve 1 shown in which a valve inlet 12th , a first valve outlet 4th and a second valve outlet 8th in a valve body 3 are provided. These openings are by means of a valve slide 15th , which along the valve axis shown 14th Can be actively moved back and forth, controllably opened and closed. In the state shown is the first valve outlet 4th closed by an associated first contact surface 30th against the corresponding first seating system 7th is pressed, which is the first seat contact pairing 5 form. This is achieved by using an actuating force 26th the valve slide 15th is shifted from left to right in the illustration. As a result, a slide lock is inserted (here for easy installation) 40 , for example a locking ring, held separate sleeve-like slide shoulder 39 of the valve slide 15th against a first energy storage element 33 , executed here as a compression spring. The first energy storage element 33 in turn pushes the first slide element 6 against the first seat 7th . Both the second valve outlet are in this state 8th as well as the tax opening 13th open. In this embodiment the pressure is at, for example a constant, supply pressure 25 at the valve inlet 12th by means of a control edge 28 of the closing element 29 controllable. The closing element 29 is with the valve slide 15th axially fixed, for example formed in one piece. As soon as a desired operating pressure at the second valve outlet 8th or in an actuation unit 20th (compare 5 ) is applied, the valve slide is 15th shifted further to the right, so the first seat contact pairing 5 overpressed and the first energy storage element 33 further compressed until or until a second contact surface 31 of the second slide element 10 against a corresponding second seating system 11 is pressed. It is true that the tax opening is also at the same time 13th briefly opened further, i.e. the volume flow and the pressure increase, but this does not impair the function for most applications. As soon as the second valve outlet 8th is closed, there is a set operating pressure in the second valve outlet 8th durable. When the pressure in the second valve outlet 8th should be drained again, the valve slide 15th move to the left again, in the embodiment shown passively by means of a third energy storage element 35 , which by means of the closing element 29 on the valve slide 15th acts and in the closed state of the actuating force 26th has been stretched. Because behind the closing element 29 a lifting chamber is to be provided, which cannot be adjusted completely leak-free, there is still a relief channel there 37 provided, which for example also with an overflow tank 38 is connected (compare 5 ). Thus, with this embodiment of a control valve 1 a high dynamic can be mapped, while at the same time an operating pressure with reduced pressure at the valve inlet 12th by means of the first slide element 6 and the second slide element 10 is durable.

In 2 is a second embodiment of a control valve 1 shown, which functionally has the same structure as the embodiment in 1 shows. In this respect, reference is made to the description there. In contrast to this, the relative displaceability is on the first pair of seat contacts 5 built in reverse; namely is the first seating system 7th on an (outer) sleeve 49 formed, the outer sleeve 49 biased by means of the first energy storage element 33 relative to the valve body 3 is axially displaceable. The corresponding first contact surface 30th however, is like the second contact surface 31 and the control edge 28 to the valve slide 15th axially fixed. Independent of this, there is also an (inner) sleeve 50 provided which like the outer sleeve 49 biased by means of a second energy storage element 34 relative to the valve body 3 is axially displaceable. This allows fine adjustment of the axial distance between the first pair of seat contacts 5 and the control edge 28 possible. In a preferred embodiment, sets the second energy storage element 34 after being inserted once, it represents the second pair of seat contacts 9 or the second seating system 11 softening spring element 19th Such a single insert is preferred solely by means of an assembly force 27 feasible, the assembly force 27 is greater than the actuating force 26th to operate the control valve 1 or the valve slide 15th .

In 3 is another embodiment of a control valve 1 with the functions described above in relation to the embodiments of 1 and the 2 shown. In this respect, reference is made to the description there. In contrast to the embodiment according to 2 is this embodiment with two bypass channels 16 , 17th executed, whereby a separation of volume flow and control pressure is created. Furthermore, in contrast to the embodiment according to FIG 2 the valve inlet 12th between the first valve outlet 4th (left) and the second valve outlet 8th (right) arranged. The first bypass channel 16 connects the valve inlet 12th and the second valve outlet 8th . The second bypass channel 17th connects the first valve outlet 4th with the first seat contact pairing 5 and at the same time forms a relief channel 37 . The first slide element 6 is now on the far right of the display. The second slide element 10 is adjacent to the first slide element on the left 6 arranged. The second slide element 10 or the corresponding paragraph on the valve slide 15th is on the opposite side (left) with the control edge 28 executed, so at the same time the closing element 29 . Both the first seat contact pairing are in the state shown 5 as well as the second seat contact pairing 9 closed. The tax opening 13th is open. An operating pressure at the second valve outlet 8th is not degradable because the first seat contact pairing 5 is closed and not via a second bypass channel 17th to the first valve outlet 4th can drain. A supply pressure 25 at the valve inlet 12th cannot go to the first valve outlet 4th drain because there is a slide gate 36 is provided. If now the valve slide 15th is shifted to the left from the state shown, is via the first bypass channel 16 a communicating connection is created by the second slide element 10 from the first bypass channel 16 is bridged. Then there is an operating pressure at the second valve outlet 8th buildable. When the valve spool 15th is shifted even further to the left, then the first (as in 2 axially preloaded) valve outlet 4th opened and via the second bypass channel 17th is a communicating connection to the first valve outlet 4th Approved. Then the pressure builds up at the second valve outlet 8th from.

In 4th is one embodiment of a control valve 1 shown which the embodiment according to the illustration in 3 is similar. In this respect, reference is made to the description there. In contrast to the embodiment according to 3 is another opening at the first valve outlet 4th created by the slide gate 36 is held closed in the position shown. When the slide gate 36 is shifted further to the left, this additional opening becomes the first bypass channel 16 opened, but at the same time or shortly before the control opening is opened 13th of the valve inlet 12th of the closing element 29 closed. The second valve outlet 8th becomes the other side of the first bypass channel 16 opened by the second slide element 10 from the second seating area 11 is lifted. This means that the pressure at the second valve outlet is reduced 8th directly via the first bypass channel 16 allows which the second slide element 10 bridged. The second bypass channel 17th is then a pure relief channel 37 and a permanent (not leak-free) gap seal 18th is at the first seat contact pairing 5 created.

In 5 is purely schematically an actuator system 2 with a control valve 1 for example according to an embodiment according to an embodiment 1 to 4th shown. Here is a friction clutch 21st by means of a hydraulic actuation unit 20th actively opened or closed. The friction clutch 21st includes an axially fixed counter plate 44 and an axially displaceable pressure plate 43 and a friction disk that can be connected in a purely frictional manner to transmit torque 45 . The actuation unit 20th acts by means of an actuating piston 42 on the pressure plate 43 via a disc spring 46 (or a diaphragm spring). The actuating piston 42 is from the in the actuating cylinder 41 introduced hydraulic fluid moved axially. The actuating cylinder 41 is via an actuation line 51 with the actuation connection 24 of the control valve 1 connected and can thus be controllably supplied with a volume flow or a control pressure. The control valve 1 in turn is via a supply connection 48 from a hydraulic supply device 22nd , shown here with a pump, with a supply pressure 25 applied. Via the tank connection 23 can hydraulic fluid into the overflow tank 38 flow away. The actuation connection 24 is at the second valve outlet 8th , the tank connection 23 at the first valve outlet 4th and the supply connection 48 at the valve inlet 12th arranged. For the sake of completeness, there is also the relief channel 37 or a separate line for relief to the overflow tank 38 shown. From the tank connection 23 is a tank line 52 to the overflow tank 38 educated. From the overflow tank 38 is (preferably) a supply line 53 to the hydraulic supply device 22nd intended. The control valve 1 or the valve slide 15th are by means of an actuator 47 can be actuated and thus an operating pressure in the actuating cylinder 41 controllable, for example based on a constant supply pressure 25 at the supply connection 48 , at least when the valve inlet 12th is open, and a set operating pressure is independent of a supply pressure 25 at the supply connection 48 from the control valve 1 durable.

In 6 is a flow chart of an operating method in an advantageous embodiment for an actuator system 2 , such as in 5 shown, shown. If you wish to increase the operating pressure, first i. in the valve inlet 12th a supply pressure 25 provided, for example by a hydraulic supply device 22nd is actively controlled.
In step ii. the valve inlet 12th and the second valve outlet 8th open.

The first valve outlet 4th will be closed if not already closed.
This is done by the actuator 47 a corresponding actuating force 26th on the valve slide 15th exercised.
Now in step iii. the operating pressure at the actuation connection 24 and thus in an actuating cylinder 41 build, for example, the friction clutch 21st according to 5 actively open.
If the operating pressure has built up as required, then in step iv. the valve inlet 12th and the second valve outlet 8th closed. The first valve outlet 4th remains closed by the first seat contact pairing 5 is overpressed. The force 26th of the actuator 47 is further increased or an increased travel of the actuator 47 queried.
In an optional step vi. is after step iv. the supply pressure 25 the hydraulic supply device 22nd at the valve inlet 12th dismantled, for example by the hydraulic supply device 22nd is switched off. Due to the lower fluidic forces on the valve slide 15th then the actuating force is preferred 26th of the actuator 47 on the valve slide 15th decreased. There is now a reduction in the operating pressure in the actuation connection 24 desired, for example a (passive) closing of the friction clutch 21st , then in a step v. the first valve outlet 4th and the second valve outlet 8th opened while the valve is running in 12th is kept closed. The pressure in the actuation unit 20th builds up when the hydraulic fluid drains into the overflow tank 38 from. If an operating pressure is to be maintained over a long period of time and is the leak in the control valve 1 , in the actuation unit 20th and / or in the actuation line 51 too big, steps iii. and iv. (and optionally vi.) repeated. If the build-up of an operating pressure is to be canceled at any point in time in the operating method, the current step is canceled and step v. executed.

In 7th Fig. 13 is a flowchart of an adjustment process of the control valve 1 as it is for example in 1 to 4th is shown. First, in a step a. the valve slide 15th into the valve body 3 inserted. This step a. is for example an upstream assembly step in a separate assembly process. The adjustment process is preferably integrated into an assembly process. Alternatively or additionally, the adjustment process is integrated into maintenance.

In a subsequent step b. comes with an assembly worker 27 the first slide element 6 as long as against the corresponding first seating system 7th and / or the second slide element 10 against the corresponding second seating system 11 pressed up in a parallel in step c. carried out monitoring of the tightness of the first seat contact pairing 5 and / or the second seat contact pairing 9 in one step d. a sufficient tightness at the first seat contact pairing 5 or the second seat contact pairing 9 is reached. Then step b. canceled. The control valve 1 is adjusted. In a preferred embodiment, the control valve is 1 already pre-adjusted in the assembly process that the control valve 1 already works and in the adjustment process only the tightness is improved. The adjustment in the adjustment process is then also referred to as fine adjustment.

With the control valve and operating method proposed here, as well as the adjustment method, efficient operation of an actuating unit is made possible in a small installation space at low cost.

List of reference symbols

1

Control valve

2

Actuator system

3

Valve body

4th

first valve outlet

5

first seat contact pairing

6

first slide element

7th

first seating system

8th

second valve outlet

9

second seat contact pairing

10

second slide element

11

second seating system

12th

Valve inlet

13th

Tax opening

14th

Valve axis

15th

Valve spool

16

first bypass channel

17th

second bypass channel

18th

Gap seal

19th

Spring element

20th

Actuation unit

21st

Friction clutch

22nd

hydraulic supply device

23

Tank connection

24

Actuation connection

25

Supply pressure

26th

Actuating force

27

Assembly force

28

Control edge

29

Closing element

30th

first contact surface

31

second contact surface

32

Through opening

33

first energy storage element

34

second energy storage element

35

third energy storage element

36

Slide gate

37

Relief channel

38

Overflow tank

39

Slider heel

40

Slide lock

41

Actuating cylinder

42

Actuating piston

43

Pressure plate

44

Counter plate

45

Friction disc

46

Disc spring

47

Actuator

48

Supply connection

49

outer sleeve

50

inner sleeve

51

Actuation line

52

Tank line

53

supply line

Claims (9)

Control valve (1) with a valve axis (14) for a hydraulic actuator system (2), having at least the following components: a valve body (3) with a first valve outlet (4), with a second valve outlet (8) and with a valve inlet ( 12), the valve inlet (12) having a control opening (13); and - a valve slide (15) which is actively movable along the valve axis (14) and has a first slide element (6) and a second slide element (10), the first valve outlet (4) having a first seat system (7) and the second valve outlet (8) ) comprises a second seat system (11), and wherein the first slide element (6) with the first seat system (7) has a first seat contact pairing (5) and the second slide element (10) with the second seat system (11) has a second seat contact pair (9) forms, wherein the valve slide (15) is set up to close and open the seat contact pairs (5, 9) and to control the valve inlet (12), characterized in that the first seat contact pair (5) is axially relative to the second seat contact pair (9). is movable. Control valve (1) Claim 1 , wherein the first seat system (7) is axially fixed and the first slide element (6) is axially displaceable relative to the valve slide (15), and preferably the second seat system (11) is axially fixed and the second slide element (10 ) is axially fixed relative to the valve slide (15). Control valve (1) Claim 1 , wherein the first slide element (6) is axially fixed relative to the valve slide (15) and the first seat system (7) is axially displaceable relative to the valve body (3), and preferably the second slide element (10) relative to the The valve slide (15) is axially fixed and the second seat system (11) is axially displaceable relative to the valve body (3). Control valve (1) according to one of the preceding claims, wherein the second slide element (10) is set up to open and close the valve inlet (12) and to open and close the second seat contact pairing (9), a first bypass channel (16) den open valve inlet (12) and the opened second seat contact pairing (9), and wherein the first slide element (6) is set up to open and close a second bypass channel (17), the second bypass channel (17) the the opened first seat contact pairing (5) and the opened second seat contact pairing (9) connects, and the first seat contact pairing (5) and the second seat contact pairing (9) are preferably connected by means of the first bypass channel (16) when the valve inlet (12) is closed, and particularly preferably the first slide element (6) permanently forms a gap seal (18) to the second bypass channel (17). Control valve (1) according to one of the preceding claims, wherein the seat system (7, 11) of the axially displaceable seat contact pair (5.9) is designed to be axially softer than the corresponding slide element (6, 10) and the seat system (7, 11) is made with an axial oversize, so that the seat system (7, 11) is permanently axially displaced by the corresponding slide element (6, 10) at least when the corresponding valve outlet (4, 8) is closed for the first time, and preferably the seat system (7, 11) is formed axially softer than the corresponding slide element (6, 10) by means of a spring element (19), and particularly preferably the spring element (19) is mechanically fixed in a displaced state. Actuator system (2) for an actuating unit (20) of a friction clutch (21), having at least the following components: - A control valve (1) according to one of the preceding claims; - A hydraulic supply device (22) which is connected to the valve inlet (12); - A tank connection (23) which is connected to the first valve outlet (4); and - An actuation connection (24) which is connected to the second valve outlet (8), with the first valve outlet (4) and the second valve outlet (8) being closable at the same time by means of the valve slide (15) when the operating pressure builds up in the actuation connection (24) . Operating procedure for an actuator system (2) according to Claim 6 , comprising the following steps in the order listed: i. providing a supply pressure (25) for the hydraulic supply device (22) at the valve inlet (12); ii. Opening or holding open the valve inlet (12), opening or holding open the second valve outlet (8) and by means of an increased actuating force (26) on the valve slide (15) closing or holding closed the first valve outlet (4); iii. building up a pressure in the actuating connection (24) until an operating pressure is reached; iv. by means of a further increased actuating force (26) on the valve slide (15) closing the valve inlet (12), closing the second valve outlet (8) and keeping the first valve outlet (4) closed; and V. if a reduction in the operating pressure in the actuation connection (24) is desired, opening the first valve outlet (4) and the second valve outlet (8). Operating procedures according to Claim 7 , further comprising a step vi. after step iv .: reducing the supply pressure (25) of the hydraulic supply device (22) at the valve inlet (12), the actuating force (26) on the valve slide (15) then preferably being reduced. Adjustment procedure for a control valve (1) according to Claim 5 , comprising the following steps in the order listed: a. Pushing the valve slide (15) into the valve body (3); b. axially pressing the first slide element (6) against the corresponding first seat system (7) and / or the second slide element (10) against the corresponding second seat system (11) with an assembly force (27); c. during step b., detecting the tightness of the first seat contact pairing (5) and / or the second seat contact pairing (9); and d. as soon as the first seat contact pairing (5) and / or the second seat contact pairing (9) is sufficiently tight, step b is canceled.

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