DE19629582A1 - Device for stabilizing the roll of a vehicle - Google Patents

Abstract

The invention relates to means for reducing the roll inclination of a vehicle with at least one axle having at least two wheels, said axle being provided with a transverse stabiliser which comprises two stabiliser sections rotatable with respect to each other by means of hydraulic means actuated by electronic control means. Said means also has at least one pump supplying the hydraulic means, valve means which co-operates with the hydraulic means and influences the torsion direction and coupling of the stabiliser sections. Said means is characterised in that the valve means (17) comprises a reversing valve (19) and a safety valve (21) operable independently thereof.

Description

The invention relates to a device for Vermin change in curl of a vehicle with at least least one having at least two wheels Axle, which is equipped with a cross stabilizer, according to the preamble of claim 1 and Einrich to reduce the tendency of a driver to curl stuff with at least two at least two wheels having axis according to the preamble of the claims 7 and 14.

Facilities of the type mentioned here are knows. They serve the suspension of a vehicle with one-sided compression and rebound of the one Axis associated wheels harden and thus a torsional vibration of the vehicle around its Avoid longitudinal axis. Such vibrations are also known as rolling or swaying. The known devices have a hydraulic direction, in particular a swivel motor, on the interacts with two stabilizer sections so that mutual twisting is effected. The the torques generated by this act as an admission tion of a frame connected to the anti-roll bar the opposite.

It has been found that not in all cases len optimal functional reliability of such Facilities can be guaranteed.

It is therefore an object of the invention, a Einrich to prevent a vehicle from curling of the above kind to create this after parts does not have.

To accomplish this task, a facility is created proposed that mentioned in claim 1 Features. The facility stands out characterized in that the hydraulic device a Ven Tileinrichtung having a switching valve and a safety valve that can be operated independently includes. The changeover valve serves the hydrau to control the lik facility so that it can also move faster Follow opposite torques in the Ab cuts of the cross stabilizer are initiated can. The safety valve has the task of a failure of the hydraulic device ordered control device the hydraulic device in a defined functional state to lead. It has been found that the order switching valve, for example due to a Ver contamination of the hydraulic fluid, can jam. The fact that the hydraulic device and includes a safety valve, one from the other are separated, a functional impairment of the order switching valve the security of the device Does not affect the reduction in curl, there is a separate independent safety valve is provided.

An embodiment of the A is preferred direction, which is characterized in that the Si safety valve the last functional element in the hydraulic supply of the hydraulic device is. The hydraulics are usually between them  device supplying pump and hydraulics establishment itself featured several functional elements see, for example facilities for recording and influencing the hydraulic flow and the Print error in one or more of these sy systems can lead to sustained security losses to lead. The safety valve is immediately in front arranged the hydraulic device, all between the pump and the safety valve the error states are intercepted.

Further configurations result from the rest against subclaims.

The task is also carried out by a facility Reduction of the curl of a vehicle ge solves that at least two each at least two Axles with wheels, axles assigned to the axles Anti-roll bars and hydraulic equipment around sums up. So it is especially Per motor vehicles with such a one direction are provided. The facility draws is characterized in that the hydraulic devices of the two axes with valve devices are, where independently acting, separate changeover and safety valves provided hen are. This results in the abge above acted security benefits.

Further configurations result from the rest against subclaims.

The task is also carried out by an institution to reduce the curl of a vehicle solved with at least two axes that also comprises a current dividing device that the of the  Pump delivered and the hydraulic equipment divides the oil flow supplied to the axles. The one direction is characterized in that the pump is designed as a volume flow limited pump, the maximum hydraulic power to be pumped likstrom limited. One works with this pump Power divider together, which is a current controller includes. This is designed so that first one of the hydraulic devices a preferably almost constant hydraulic oil power is supplied until the current controller responds and the hydraulic connection between the pump and the second hydraulic device releases. A derar tig trained current divider is very insensitive to vibrations. Conventional electricity divider devices are as classic current dividers formed and have two control edges, from which one of the supply of the one hydraulic direction and the other of supplying the second Hydraulic device is assigned. The one from the Hydraulic flow delivered is always at the pump Control edge regulated that of the hydraulic device associated with the lower pressure. Are the Pressures of the two hydraulic devices approximately same size, it comes due to the valve hysteresis to uncontrolled control edge changes. This ge Mutual coupling-related influencing of the the fluid flows causes the flow divider is sensitive to vibration and tolerance. Through the Design proposed here, namely by the combination of a volume flow limited pump With a current regulator, vibration and tole ranz problems can be significantly reduced.

An embodiment is particularly preferred the facility, which is characterized in that  that assigned in the first hydraulic device Current path a first pressure regulator and that of the two Current path associated with the hydraulic device second pressure regulator is assigned. The one you want So pressure can be independent in the two current paths dependent on each other.

An embodiment of the device is preferred tion, which is characterized in that the first and Kopop second pressure regulator over the current regulator pelt and that the current regulator with an as Pressure relief valve acting pressure pilot is, which preferably acts mechanically. Through the Coupling of the two pressure regulators ensures that if one of the pressure regulators fails, the other the pressure of both current paths is applied and acts as a pressure relief valve. It can an additional security against sudden pressure peaks and excessive pressure values in the Hydraulic system can be created. It is possible to push the pressure pilot into the current regulator tegrate and thus a very compact design to reach.

The invention is based on the drawing tion explained in more detail. Show it:

Fig. 1 is a hydraulic diagram of a device for avoiding the tendency of curling of a traveling toy comprising at least two wheels with an axis;

Fig. 2 is a hydraulic diagram of a device for avoiding the tendency to curl of a vehicle with at least two axles each having at least two wheels;

Fig. 3 is a schematic diagram of a Umschaltven valve and

Fig. 4 is a schematic diagram of a safety valve.

The ones described below as anti-roll Stabilization or active roll stabilization be signed facility to avoid the roll The inclination of a vehicle is for all vehicle types usable, the at least one two wheels include pointing axis. So it is conceivable that Use equipment for so-called "trikes".

In Fig. 1 the hydraulic diagram of a device for vehicles is shown, which have only one axis. Fig. 2 shows a hydraulic diagram for a vehicle with two axles.

The device 1 shown in Fig. 1 comprises a hydraulic device 3, which may for example comprise a pivot motor. This Schwenkmo gate is symbolically indicated here by a double-acting cylinder, which comprises a reciprocating piston 5 , which acts via control rods 7 and 9 on stabilizer sections, not shown here, of a transverse stabilizer. These sections are part of a cross stabilizer, which is designed in wesentli Chen U-shaped and whose legs engage with the ends of the axle or on the suspension of the wheels assigned to the axle. The U-shaped base of the anti-roll bar is separated on. The ends are connected to each other via the Hydraulikein direction. The Hydraulikein direction is designed in a known manner so that the stabilizer sections can be rotated against each other, so that torques are generated in the Querstabilisa gate. These influence the deflection and rebound of the wheels.

The hydraulic device 3 is supplied with hydraulic fluid by a pump 11 via suitable hydraulic lines 13 . This is conveyed from a tank 15 only indicated here. The pump 11 is designed here as a suction-throttled pump which has a throttle on its suction side. An approximately constant volume flow can also be generated by volume flow control of a constant or variable pump on the hydraulic side or by influencing the pump drive. The hydraulic fluid is supplied to the hydraulic device 3 via a valve device 17 . The valve device comprises a changeover valve 19 and a safety valve 21 . The switching valve 19 is designed as a 4/2-way valve. A first line section 23 leads via a second line section 25 and via a third line section 27 into a first pressure chamber 29 of the hydraulic device 3 . From a second pressure chamber 31 , a fourth line section 33 leads via the safety valve 21 to a fifth line section 35 , which leads to the tank 15 via the changeover valve 19 .

The valves of the valve device 17 are designed here as electromagnetically operated valves which have a preferred position. The safety valve 21 is provided with a spring 37 which urges the control piston of the safety valve, which is only indicated here, against the force of a magnetic device M1 to the left. Accordingly, the switching valve 19 is seen with a magnetic device M2, which acts against a spring 39 . This urges the control piston of the switching valve indicated here to the left into a preferred functional position. These functional positions of the switchover valve and the safety valve shown here are assumed in the deactivated or currentless state of the magnetic devices M1 and M2. It can be seen from the illustration in FIG. 1 that in this position the first line section 23 is connected to the second line section 25 and the fifth line section 35 is connected to the tank 15 . The safety valve 21 is designed so that the connection between the second line section 25 and the third line section 27 and between the fourth line section 33 and the fifth line section 35 is blocked in the de-energized state. In operation of the device 1 , the magnetic device M1 of the Si safety valve 21 is activated, so that the control piston of the safety valve is displaced to the right against the force of the spring 37 , so that, as indicated by arrows, a hydraulic connection between the line sections 25 and 27 such as 33 and 35 . When the device is operating correctly, this hydraulic connection is continuously established.

So speaks of the solenoid device M1 controlled safety valve 21 in normal operation, a hydraulic connection between the pump 11 and the first pressure chamber 29 via the hydraulic line 13 and via the line sections 23 , 25 and 27 is made. At the same time there is a hydraulic connection between the second pressure chamber 31 via the line sections 33 and 35 to the tank 15 .

If the switching valve 19 is controlled via the Magneteinrich device M2, the Steuerkol ben of the switching valve moves against the force of the spring 39 to the right, so that the first line section 23 , as indicated by crossed arrows, is connected to the fifth line section 35 while the second line section 25 is connected to the tank 15 . In this way, the pressure loading of the piston 5 is reversed. It is now the first pressure chamber 29 opposite second pressure chamber 31 with the hydraulic oil supplied by the pump 11 acted upon. Depending on the pressure applied to the pressure chamber 29 and 31 , the piston 5 moves to the right or left. Due to the reciprocating movement of the piston 5 , opposing moments are introduced into the stabilizer sections of the transverse stabilizer.

The control of the magnetic devices M1 and M2 takes place via a control device 41 , which is only indicated here.

In the hydraulic line 13 , a pressure regulator 43 is integrated, which is designed as a proportional pressure relief valve and via which the pressure prevailing in the hydraulic line 13 is continuously adjustable. The pressure regulator comprises a magnetic device M3 which acts against the pressure applied to a control piston via a control line 45 and, at an adjustable excess pressure, delivers hydraulic oil via a relief line 47 to the tank 15 .

The magnetic device M3 can be controlled via a suitable control line with the help of the control device 41 .

Fig. 1 also shows a pressure sensor 49 which detects the pressure generated by the pump 11 . The sensor is arranged here by way of example in the first line section 23 . It is connected via an electrical line not shown here to the Steuereinrich device 41 , which detects the output signals of the sensor and for controlling the valves, for example the safety valve 21 , evaluates.

Fig. 1 finally shows that in the control device 41, a signal line 51 leads, via which signals are input which, for example, reflect the cornering position and speed of the vehicle, due to which a torque in the Stabilisierungsab sections is initiated via the Hydraulikein device 3 . The torque is dependent on the spring condition of the wheels. Opposing moments may be required in rapid succession, which can be achieved by switching over the pressure conditions given in the pressure chambers 29 and 31 . The reversal of the pressure conditions is achieved with the aid of the changeover valve 19 , which is controlled via the control device 41 . By activating the changeover valve 19 accordingly, moments can be introduced into the stabilizer sections which counteract rolling or swaying of the vehicle.

Fig. 2 shows a hydraulic diagram of a device for reducing the roll tendency of a vehicle with two axles. It can be seen that on the left-hand side of the illustration, the components are repeated which were already explained with reference to FIG. 1. The device 1 is, for example, designed so that the parts explained with reference to FIG. 1 here are assigned to a front axle of the vehicle, not shown here. A second hydraulic device 3 ', which is constructed almost identically, as the hydraulic device 3 explained in Fig. 1 and which is arranged to the rear axle, comprises a piston 5 ' and control rods 7 'and 9 '. The hydraulic device 3 'can thus, like the hydraulic device 3 described in FIG. 1, also comprise a swivel motor, which is shown here merely as an illustration of the effect of the device 1 ' as a double-acting cylinder. The first pressure chamber 29 'is connected via a third line section 27 ' and via the safety valve 21 'in the functional position shown here with the tank 15 . Likewise, the second pressure chamber 31 'is connected via a line section 33 ' and the switching valve 19 'to the tank 15 . In the currentless state of the Ventileinrich device 17 shown here, both pressure chambers 29 'and 31 ' of the hydraulic device 3 'are connected to the tank, so that no moments can be introduced into the stabilizer sections.

In the functional state shown here, the line section 23 ', which continues via the switching valve 19 ' in the line section 25 ', is completed by the safety valve 21 '. The hydraulic connection between the pump 11 and the hydraulic device 3 'is thus interrupted in the functional position of the Ventilein device 17 shown here.

Fig. 2 shows the valve device 17 , so also the safety valve 21 'and the switching valve 19 ' in the inactivated state, which results, for example, in the event of a power failure or when an error is detected via the control device 41 and the valve device from the power supply is separated.

In normal operation, however, the control piston of the safety valve 21 'against the force of the Fe of 37 ' is moved to the right, so that the section 25 'is connected to the line section 27 '. In this functional position, the switch valve 19 'is fully functional. In the activated state of the valve device, the hydraulic line 13 'via the line section 23 ', the switching valve 19 ', the line section 25 ', the safety valve 21 'and the line section 27 ' with the first pressure chamber 29 'of the hydraulic device 3 ' is connected . At the same time, the second pressure chamber 31 'via the line section 33 ' and the switching valve 19 'is connected to the tank 15 . A on the hydraulic line 13 'prevailing pressure thus moves the piston 5 ' to the left, since the left pressure chamber 31 'is entla st.

When the switch valve 19 is activated, if pressure is present on the hydraulic line 13 ', the second pressure chamber 31 ' via the line section 23 ', the switch valve 19 ' and via the line section 33 'are pressurized. At the same time, the first pressure chamber 29 'via the line section 27 ', the safety valve 21 ', the line section 25 ' and the Umschaltven valve 19 'connected to the tank 15 and thus relieved of pressure. If, for example, the case arises that the changeover valve 19 is jammed in this position, that is to say in its right end position, and thus would no longer be switchable, the pressure in the pressure chamber 31 'and the line section 33 ' can be obtained via the pressure regulator 43 'Are broken down.

From Fig. 2 it can be seen that the safety valves 21 and 21 'and the switching valves 19 and 19 ' of the valve device 17 are rigidly coupled via a rod 81 . The rod 81 serves le diglich here to illustrate the coupling of the switching valves. The activation and deactivation of the safety valves - like that of the changeover valves - is carried out simultaneously. It turns out, however, that the safety and Umschaltven tile of the valve device 17 are mechanically completely decoupled from each other. The very frequent switching functions of the switching valve, which can lead to wear, do not in any way affect the safety valve. Of course, this also applies to the device shown in FIG. 1. So it can be caught on Umschaltven valve 19 , 19 'occurring malfunctions by the safety valve 21 , 21 '. Be particularly advantageous is that a malfunction of the safety valve 21 , 21 'can not lead to a critical driving condition.

Fig. 2 shows that in the line section 23 ', as in the left part of the device 1 ' of FIG. 2, a pressure sensor 49 'is provided, which is connected to the control device 41 via a line, not shown here.

In the hydraulic line 13 'is also a pressure regulator 43 ' introduced, which includes a Magnetein direction M3 ', which acts against the pressure that is given in the hydraulic line 13 ' and via the control line 45 'to the pressure regulator 43 ' is attached becomes.

The elements shown on the left in FIG. 2, the hydraulic device 3 , the safety valve 21 and the changeover valve 19 of the valve device 17 are assigned to the front axle. Their structure is identical to that of the device explained with reference to FIG. 1, so that this structure is not discussed in more detail here. The same parts are provided with the same reference numbers. Correspondingly, reference numerals marked with a dash are selected for the parts of the rear axle, which are shown on the right in FIG. 2.

The hydraulic diagram of Fig. 2 shows that the hydraulic devices 3 and 3 'of the front and rear axles are supplied likflüssigkeit by a single pump 11 Hydrau. In order to guide the fluid flow supplied by the pump to the front and rear axles or to the associated hydraulic devices 3 and 3 ', a flow divider device 53 is provided which comprises a current controller 55 . The current regulator 55 is equipped with a pressure relief valve 69 , referred to as a pressure pilot, which is connected via a control line 71 and a throttle 73 to the hydraulic line 13 and since to the pressure outlet 59 of the pump 11 . Print pilots of the type mentioned here are known. For example, they have a ball 75 which is pressed against a valve seat 79 by a spring 77 . At an overpressure which is above a value defined by the spring 77 , the ball 75 lifts off the valve seat 79 so that oil can flow out to the tank 15 . The pump 11 is here provided with a suction throttle 57 , which keeps the fluid flow delivered from the tank 15 at a predetermined maximum value.

The hydraulic line 13 is connected here to the pressure outlet 59 of the pump 11 via a throttle D1. A line section 61 leads directly from the pressure outlet 59 to the flow regulator 55 , the control piston 63 of which is acted upon on the one hand by the force of a spring 65 and the pressure prevailing in the control line 71 , and on the other hand via a control line 67 with the pressure given at the pressure outlet 59 . In the depressurized state, the control piston 63 separates the line section 61 from the hydraulic line 13 ', which serves to supply the rear axle.

If the pump 11 is put into operation, the control piston 63 is finally shifted to the left into the control position by the pressure applied via the control line 67 against the force of the spring 65 and the pressure prevailing in the control line 71 . By relocating the control piston 63 , a fluid connection from the pressure outlet 59 of the pump 11 via the line section 61 , via the flow controller 55 to the hydraulic line 13 'is released, so that now the pressure chambers 29 ' and 31 'of the hydraulic device 3 ', depending on the position of the To switch valve 19 ', alternately pressurized can be beat.

The pump '11 works preferably while driving in the control area, that is, it promotes a constant volume flow. The flow controller 55 preferably primarily provides the hydraulic device 3 , that is to say the front axle, with a constant volume flow.

The pressure regulators 43 and 43 'are designed such that a pressure of approximately 0 bar to 200 bar can be set via the control device 41 . It is ensured that the pressure supplied to the front axle, which is also supplied to the hydraulic device 3 , is at least equal to or greater than the pressure applied to the hydraulic device 3 ', which is provided for the rear axle.

The hydraulic diagram according to Fig. 2 reveals that the hydraulic device 3 of the front axle and of the hydraulic device 3 are assigned to 'the rear axle separate pressure regulators 43 and 43', which communicate with the hydraulic lines 13 and 13 'in the hydraulic connection and the establishment of the control 41 are controlled and when the predetermined pressure is exceeded hydraulic oil can flow through the relief lines 47 and / or 47 'to the tank 15 .

The pressure regulators 43 and 43 'are coupled here so that in the event of a failure of one of the pressure regulators, the other serves as a pressure relief valve for the entire system, that is to say also for the other hydraulic line. In the device 1 'shown in Fig. 2' a coupling via the Stromteilereinrich device 53 or via the current controller 55 in cooperation with the pressure valve referred to as a pressure pilot 69 is provided. This coupling works as follows:
After the pump 11 has started, the connection between the line section 61 and the hydraulic line 13 'of the rear axle is interrupted by the current controller 55 or its piston 63 . The hydraulic oil provided by the pump is therefore supplied to the hydraulic device 3 via the hydraulic line 13 . When the pressure difference at the throttle D1 increases within the hydraulic system, the current controller 55 finally responds, the control piston 63 releasing the hydraulic connection to the hydraulic line 13 '. So that the second pressure regulator 43 'is supplied with oil. The two pressure regulators 43 and 43 'are set so that the pressure provided for the front axle is equal to or greater than that of the rear axle. If, for example, the pressure regulator 43 'fails and the pressure in the hydraulic system assigned to the rear axle rises due to a fault, the pressure given in the line section 61 also increases, which then continues via the line 13 to the first pressure regulator 43 . The pressure regulator 43 can now respond and relieve excess pressure via the relief line 47 . It can be seen that the part of the hydraulic system which is assigned to the rear axle or the hydraulic device 3 'is also monitored in the event of a fault via the pressure regulator 43 , which is generally assigned to the front axle or the hydraulic device 3 .

Conversely, it is clear that in the event of a failure of the pressure regulator 43 of the hydraulic device 3, an excess pressure based on an accident is transmitted via the line section 61 to the hydraulic line 13 'and is thus detected by the second pressure regulator 43 '. This can reduce the excess pressure and let hydraulic oil flow from the relief line 47 'because the flow regulator is equipped with the pressure relief valve 69 , the line 71 via the control line 71 , the throttle 73 with the hydraulic line 13 and thus with the pressure outlet 59 of the pump 11 is connected. The in the event of a malfunction of the hydraulic device 3 'in the control line 71 , the pressure is smaller by the throttles D1 and 73 than the pressure on the control line 67 , which corresponds to the pump pressure, which enables switching of the current regulator 55 and a connection between the line 61 and the hydraulic likleitung 13 'is given.

In FIG. 2, the following aspect is also interpreting Lich: The safety valves 21 and 21 '., As in the embodiment in Figure 1, in UNMIT ately to the hydraulic device 3 be relationship as 3'. Errors in the other components, which can be seen from the hydraulic diagrams of FIGS. 1 and 2 and lead to undefined conditions, can be intercepted by the safety valve 21 or 21 '. The safety valves 21 , 21 'thus provide a fail-safe function.

In the embodiment shown in FIG. 1 and in the part of the device 1 ', which is assigned to the front axle, the piston 5 of the Hydraulikein device 3 is set hydraulically. This is done in that the safety valve 21 is shifted into the position shown in FIGS. 1 and 2, whereby the line sections 33 and 27 are separated from the rest of the system. Since hydraulic flow is no longer possible here, the hydraulic device 3 acts as a rigid coupling of the associated stabilizer sections.

In the area of the rear axle, the safety valve 21 'is moved into the position shown in Fig. 2 in the event of a fault. This is done by the spring 37 ', which displaces the control piston of the safety valves 21 and 21 ' to the left. Since by - in the current-free position of the switching valve 19 'shown in Fig. 2' - the hydraulic likeinrichtung 3 'on both sides ver with the tank 15 connected. That is, both pressure chambers 29 'and 31 ' are separated from the pump 11 and depressurized. It is conceivable here to allow free movement of the piston 5 'and thus a decoupling of the hydraulic device 3 '. However, it is also possible to introduce at least one hydraulic throttle, which prevent the hydraulic fluid from flowing freely out of the pressure chambers and thus cause damping. Such a throttle is indicated in Fig. 2 and provided with the reference symbol D2. The hydraulic device 3 'associated Stabilisa gate sections are not rigidly coupled to each other, but also not completely decoupled. So it can still torque from a Stabili satorabschnitt via the hydraulic device 3 'to the other stabilizer section who who, so that a residual function of the anti-roll bar is ensured. However, torques are no longer actively introduced into the transverse stabilizer or into its sections. A complete decoupling of the anti-roll bar is possible by eliminating throttle D2.

In Fig. 1 there is a rigid coupling in the event of a fault by the safety valve 21 , since the line sections 27 and 33 are completed. However, it is also conceivable here to provide a complete decoupling or a damped decoupling, as just described with reference to FIG. 2.

In both cases it is guaranteed that the safe safety valve due to the separate design from the um switching valve is independent and therefore a very shows high safety function.

This decoupled design of the two valves is also seen on the valve device 17 according to FIG. 2 before. There, too, the safety valves 21 and 21 'are rigidly coupled to one another and the changeover valves 19 and 19 ' to one another. However, they are completely separate and independent of each other. That is, frequent switching operations do not affect the separate safety valve, so that there is a high safety standard.

The device 1 'shown in FIG. 2 is characterized in that the current divider 53 shows little vibration and tolerance problems by the current controller provided with pressure pilot. This in turn makes a large contribution to the safety of the device shown here. Finally, the pressure regulator 43 and 43 'assigned to the rear and front axles are coupled so that in the event of a failure of one of the pressure regulators the other can also protect the entire system in the event of a fault against excessive pressure.

In the embodiment of the device 1 'shown in Fig. 2', a hydraulic line 110 is provided which has a valve unit 112 . The hydraulic line 110 is used to establish a hydraulic connection between the hydraulic devices 3 and 3 'provided pressure levels. The hydraulic line 110 therefore bridges the current divider device 53 . For this purpose, the hydraulic line 110 is here connected to the hydraulic devices 3 and 3 'with an oil flow supplying hydraulic lines 13 and 13 ', in which the same pressure level prevails as in the pressure regulators 43 and 43 'assigned to them. The Ventilein unit 112 is preferably designed as a mechanical check valve, which comprises a valve seat 114 , into which a ball 116 is pressed. The valve units are simple and functionally stable. The valve unit 112 connects the pressure levels of the two hydraulic devices 3 , 3 'preferably whenever the pressure applied to the hydraulic device 3 is less than the pressure applied to the hydraulic device 3 '. Through the valve unit designed as a check valve, a control and control device that compares the two pressure levels with one another is thus implemented, which independently regulates the pressure. In this way, in the embodiment shown in Fig. 2 switching function of the valve unit 112 is ensured at all times, that the pressure level of the hydraulic device 3 at least equal to 'pressure from the hydraulic device 3 or greater.

From the above it is clear that the valve unit compensates for the manufacturing and setting tolerances of the individual modules, for example the pressure regulator 43 , 43 ', the pump 11 and the flow divider device, which lead to an influencing of the pressure levels. Furthermore, improperly made and not desired settings of the pressure regulator are compensated by the fluid connection.

In Fig. 3 is a schematic diagram of a switching valve together with the hydraulic symbol as shown. In the illustration above is the hy metallic symbol; including a first functional position of the changeover valve and at the bottom a second functional position of the changeover valve as shown. In Fig. 3 the given in Fig. 2 given valve device with the switching valves 19 and 19 'is shown. In the schematic diagram of FIG. 2, the two sub-valves are shown separately to illustrate the function, here being rigidly coupled to one another via a rod 81 .

In the actual implementation of the Umschaltven tile 19 and 19 ', the control pistons of both Ven tiles are advantageously combined to form a control piston 83 which is guided in a cylindrical bore 85 against the force of a spring 87 . A magnetic device M2 counteracts the spring. In the wall of the bore 85 different grooves are made, which are provided here with numbers that correspond to the inputs and outputs of the switching valves 19 and 19 '. The upper connections of the switching valve 19 are marked with 1 and 3 , those of the Umschaltven valve 19 'with 4 and 6 . The lower connections of the switching valve 19 are marked with the tank symbol and the number 2 , the Umschaltven valve 19 'also with the tank symbol and the Zif fer 5 .

The corresponding hydraulic connections are guided through the wall 89 of the housing of the Umschaltven valve, which is not shown in detail here.

In the upper illustration, the control piston 83 is in an inactive state. That is, the magnetic device M2 is not activated, so that the spring 87 can move the spool 83 to the left. The control piston is provided with control surfaces which are delimited by control edges and, depending on the position of the control piston, separate or connect the annular grooves 91 serving as feed and discharge.

In the functional position of the control piston 83 shown in FIG. 3 above, the connections 3 and 2 of the changeover valve 19 and the connections 6 and 5 of the changeover valve 19 'are connected to one another. At the same time, port 1 and port 4 are connected to the tank. So there is virtually a straightforward implementation of the hydraulic connections in the two changeover valves 19 and 19 '.

If the magnetic device M2 is activated, the control piston 83 is moved to the right against the force of the spring 87 (see lower illustration), so that the following hydraulic connections now result:
Within the changeover valve 19 , the connection 3 is connected to the tank; the connections 1 and 2 are interconnected. Within the Umschaltven valve 19 ', the connection 6 is connected to the tank and the connections 5 and 4 are connected to one another. This is indicated in the hydraulic symbol at the top in FIG. 3 by the crossed arrows. It is thus ensured that the connections of the two pressure chambers 29 and 31 or 29 'and 31 ' are interchanged when the switching valve responds. As a result, opposing moments are initiated by the hydraulic devices 3 and 3 'in the associated stabilizer sections.

Fig. 4 shows the safety valves 21 and 21 ', which are shown in Fig. 2. To connect the two sub-valves, a rod 92 is also provided here, which effects a rigid coupling of the two control pistons.

Such a safety valve is advantageously implemented in such a way as can be seen in the two un lower representations according to FIG. 4. There is a continuous piston 93 housed in a cylindri's bore 95 , in the wall of which annular grooves 97 are introduced, which interact with hydraulic connections, not shown here. The piston 93 has control collars and control edges through which the ring grooves can be connected to one another in different ways.

The annular grooves 97 are assigned to the connections of the safety valves, which are identified here with numbers. The safety valve 21 has two upper connections 2 and 4 and two lower connections 1 and 3 , while the safety valve 21 'has an upper connection 6 and two lower connections 5 and 7 , the connection 7 being connected to the tank, which is illustrated here by the tank symbol.

The safety valve here has a Magnetein device M1, which acts on the piston 93 , which is shifted to the right against activation of the magnetic device M1 against the force of a spring 99 . In the upper schematic diagram, the piston 93 is shown in its inactivated position. That is, the magnetic device M1 is de-energized so that the spring 99 can push the piston 93 to the left. In this functional position, as seen from the Prin Fig. 4 zipskizze according recognizable given a hydrau metallic separation of the terminals 1 and 2 and the terminals 3 and 4, as shown in the safety-valve 21. At the same time there is a hydraulic separation between the connections 6 and 5 , on the other hand there is a hydraulic connection between the connections 7 and 6 . In the fourth state of the safety valve, the magnetic device M1 presses the piston 93 to the right against the force of the spring 99 , so that there is a connection between the connections 1 and 2 and 3 and 4 of the safety valve 21 . At the same time there is a hydraulic separation of the connections 7 and 6 and a hydraulic connection between the connections 6 and 5 of the safety valve 21 '.

After all, it is clear that the Sicherheitsven tile 21 and 21 'and the switching valves 19 and 19 ' can be combined and have a common piston. This summary applies to the changeover and safety valves. However, there is no coupling between the changeover valves and the safety valves, so that there is a separation of the changeover and safety function. A malfunction of the changeover valves cannot have a negative effect on the functional safety of the safety valves.

After all, it is clear that the one described here Setup on the one hand for two-axle vehicles, cars are used in particular, on the other hand also for vehicles with one axle and at least two wheels, for example for so-called trikes. The device described here can easily be used device is also used in multi-axle vehicles will.

Claims (17)

1. A device for reducing the tendency to curl egg nes vehicle with at least one axle having at least two wheels, which is provided with a Querstabi lizer, which comprises two stabilizer sections rotatable against each other with the aid of a hydraulic device controlled by an electronic control device, with at least one supplying the hydraulic device Pump, with a valve device which interacts with the Hydraulikein direction and influences the direction of rotation and coupling of the stabilizer sections, characterized in that the valve device ( 17 ) comprises a changeover valve ( 19 ) and an independently operable safety valve ( 21 ). 2. Device according to claim 1, characterized in that the switching valve ( 19 ) is designed as a 4/2-way valve. 3. Device according to claim 1 or 2, characterized in that the safety valve ( 21 ) in egg ner first functional position connects the Hydraulikeinrich device ( 3 ) with the pump ( 11 ) and in a second functional position a rigid or a damped coupling of the Stabilizer sections or a decoupling of the stabilizer sections be effective. 4. Device according to one of the preceding claims, characterized in that the safety valve ( 21 ) is the last functional element of the hydraulic supply of the hydraulic device ( 3 ). 5. Device according to one of the preceding claims, characterized in that the switching valve ( 19 ) and / or the safety valve ( 21 ) can be actuated electromagnetically. 6. Device according to one of the preceding claims, characterized in that the switching valve ( 19 ) and / or the safety valve ( 21 ) has a preferred position. 7. Means for reducing the tendency to curl egg nes vehicle with at least two at least two wheels having axle, each provided with egg nem anti-roll bar, which includes two by means of a controlled by an electronic device Steuereinrich hydraulic device against each other the rotatable stabilizer sections, with at least one the hydraulic devices supplying pump with a valve device which interacts with the hydraulic devices and influences the direction of rotation and coupling of the stabilizer sections, characterized in that the valve device ( 17 ) has a switching valve ( 19 , 19 ') and an independently operable safety valve ( 21st , 21 ') includes. 8. Device according to claim 7, characterized in that the switching valve ( 19 , 19 ') is designed as a 4/2-way valve. 9. Device according to claim 7 or 8, characterized in that the safety valve ( 21 , 21 ') in a first functional position connects the Hydraulikein direction ( 3 , 3 ') with the pump ( 11 ) and in a second functional position a rigid or a damped coupling of the stabilizer sections or a decoupling of the stabilizer sections. 10. Device according to one of claims 7 to 9, characterized in that the safety valve ( 21 , 21 ') is the last functional element of the hydraulic supply and the hydraulic device ( 3 , 3 '). 11. Device according to one of claims 7 to 10, characterized in that the switching valve ( 19 , 19 ') and / or the safety valve ( 21 , 21 ') can be actuated electromagnetically. 12. Device according to one of claims 7 to 11, characterized in that the switching valve ( 19 , 19 ') and / or the safety valve ( 21 , 21 ') has a preferred position. 13. Device according to one of claims 7 to 12, characterized by a hydraulic line ( 110 ) connecting the hydraulic devices ( 3 , 3 ') provided pressure lines, with a valve unit ( 112 ) which releases a hydraulic connection when the one, preferably the front axle associated hydraulic device ( 3 ) applied pressure is less than the pressure applied to the hydraulic device ( 3 '). 14. Device according to one of the preceding claims, and having a flow divider influencing the hydraulic flow supplied from the pump to the axes associated hydraulic devices, characterized in that the pump ( 11 ) is designed as a volume-flow-limited pump and that the flow dividing device ( 53 ) comprises a current controller ( 55 ) which, in a first function position, the first - preferably assigned to the front axle - hydraulic device ( 3 ) and in the second operating position the second - preferably assigned to the rear axle - hydraulic device ( 3 ') with the pump ( 11 ) connects and preferably supplies the first hydraulic device ( 3 ) with an almost constant oil flow. 15. The device according to claim 14, characterized in that in the first hydraulic device ( 3 ) associated current path, a first pressure regulator ( 43 ) and in the second hydraulic device ( 3 ') associated current path, a second pressure regulator ( 43 ') is provided and that the pressure regulators are coupled to one another. 16. The device according to claim 15, characterized in that the first pressure regulator ( 43 ) and the second pressure regulator ( 43 ') are coupled via the with a pressure relief valve ( 69 ) acting, preferably mechanically trained pressure pilot provided current controller ( 55 ) . 17. Device according to one of claims 14 to 16, characterized by a hydraulic line ( 110 ) connecting the hydraulic devices ( 3 , 3 ') provided pressure lines, with a valve unit ( 112 ) which releases a hydraulic connection when the one, preferably the front axle associated hydraulic device ( 3 ) applied pressure is less than the pressure applied to the hydraulic device ( 3 ').