CN213332683U

CN213332683U - Control valve with hydraulic electric drive

Info

Publication number: CN213332683U
Application number: CN202020805383.0U
Authority: CN
Inventors: S·科尔本施拉格
Original assignee: Hercules Corp
Current assignee: Hercules Corp; Samson AG
Priority date: 2019-05-20
Filing date: 2020-05-14
Publication date: 2021-06-01
Anticipated expiration: 2030-05-14
Also published as: DE102019113358A1; DE102019113358B4

Abstract

The utility model relates to a governing valve with hydraulic pressure electric drive mechanism, its one-way effect and including two actuators, each actuator has hydraulic pressure bellows (150,160) and reaction spring (170, 180). The first actuator is fixedly connected to the valve stem (110). The second actuator has a strong spring (180) and is connected to the valve stem (110), i.e. it is entrained when it performs a movement towards the safety position and is not actively moved when it performs a reverse movement. In the event of a fault, the hydraulic oil of the second actuator flows out. The spring also moves the valve stem against the action of the first actuator to a safe position and causes a high tightening force. In normal operation, the hydraulic bellows (160) of the second actuator is filled and its spring is compressed. Only the movement of the weaker first actuator adjusts the valve position, wherein only little energy is required. The design with bellows is used for high tightness of the hydraulic system.

Description

Control valve with hydraulic electric drive

Technical Field

The utility model relates to a governing valve with hydraulic pressure electric drive mechanism.

Background

Such control valves are used primarily for limiting the fluid flow, wherein the hydraulic electric drive is capable of achieving high pressures with low energy requirements.

The control valve requires an adjustment drive for moving the control element. Depending on the application, such a drive mechanism is equipped with a function for obtaining a safety position. In the event of a failure of the power supply, the adjusting element is moved, for example, into a predetermined safety position. Typically, it is a closed position so that no more process fluid can reach through the regulator valve. In which case the regulating valve is usually required to close very tightly. In most cases, the safety function is achieved by a powerful spring, which forces the adjusting element into the safety position in the case of safety by means of a spring force.

The spring is generally always active in the case of a pneumatic or hydraulic drive. The pneumatic or hydraulic unit therefore always operates in normal operation against the action of a spring (one-way drive). The energy required to adjust the position of the valve cartridge is thus high. The shut-down function is less important in normal operation of such a control valve, since the typical drive range for regulating the process fluid moves in the open position. That is to say, the continuous movement, in contrast to the very strong return spring, requires an unnecessarily large amount of energy, wherein its large spring force is only required in the event of a fault in order for the valve to be reliably closed.

In the case of electric drives with fail-safe function, the drive is also usually spring-loaded against a safety position, i.e. must be able to generate a high force, although this is not really necessary for the adjustment process.

Drive mechanisms with a safety function, which in normal operation should not work against the safety position for a long time with spring action, are generally designed to be double-acting. An example is disclosed in DE102014019574B 3.

WO2012/073172a1 and EP77596a1 also describe a double-acting valve drive mechanism with a safety function.

SUMMERY OF THE UTILITY MODEL

The object of the invention is to specify a control valve for a hydraulic electric drive having a single-action, which has a high clamping force and still consumes little energy during normal operation, in particular as a fail-safe function.

The use of the singular should not exclude the plural and vice versa unless indicated to the contrary.

To accomplish this object, a control valve having an electrically operated hydraulic drive is proposed. The regulating valve has a valve rod which guides a valve core part and is driven by a one-way acting drive mechanism. It has at least two actuators. The at least one first actuator has at least one first hydraulic unit and at least one first reaction accumulator, is fixedly connected to the valve stem and is used for adjusting the position of the valve core member. For example, bellows or hydraulic cylinders or the like can be used as hydraulic units, while the energy store can be, for example, a spring or an air cushion. In addition, the hydraulic electric drive has a hydraulic pump for pumping hydraulic oil, which is designed such that it can fill the hydraulic units of the actuators with hydraulic oil against their respective reaction accumulators. The at least one second actuator has at least one second hydraulic unit and at least one second reaction accumulator, which together accumulate a force greater than the common accumulated energy of the at least one accumulator of the first actuator for adjusting the position of the valve core part.

Typically, the actuator consists of three bellows with respective reaction springs, which are arranged uniformly around the valve stem.

The second actuator is connected to the valve stem in such a way that the valve stem is entrained when the second actuator performs a movement towards the safety position and is not actively moved when the second actuator performs a reverse movement. There is therefore no connection between the second actuator and the valve stem that carries the valve stem when the second actuator performs a movement away from the safety position.

Furthermore, the second hydraulic unit of the second actuator is connected to a safety valve which, in the event of a fault condition, causes hydraulic oil to flow out of the second hydraulic unit of the second actuator.

This results in a strong second reaction accumulator urging the valve stem towards the safety position. As a result, a safety position is thereby occupied in the fault state.

In other respects, however, the powerful accumulator for achieving the safety position can be pretensioned by the second actuator, so that in normal operation it works against the weaker first counteracting accumulator only.

Thus, a control valve for a hydraulic electric drive with a unidirectional action exists. The second actuator provides a fail-safe function, since when the safety valve is triggered and hydraulic oil is allowed to flow out of the hydraulic unit of the second actuator, the powerful accumulator of the second actuator can move the valve stem into the safety position, if necessary, also against the action of the first actuator. The powerful accumulator accordingly also allows a large closing force. The second actuator is in the pretensioned state in normal operation, i.e. the hydraulic unit of the second actuator is filled and its accumulator is thus compressed, for example. The unidirectional and non-fixed connection of the second actuator to the valve stem ensures that in normal operation only movements of the first actuator dimensioned significantly weaker are used for adjusting the valve position. The hydraulic system requires energy only when the pressure builds up, i.e. the respective accumulator is overcome only when the valve opens. However, it is not too strong in the first actuator, since it does not exert a safety function. That is, only a small amount of energy is consumed in the adjustment.

Both actuators or hydraulic units are preferably supplied by the same hydraulic pump. However, the higher accumulation of the accumulator or accumulators of the second actuator can be overcome in such a way that the effective active surface area of the at least one hydraulic unit of the at least one second actuator is greater than the effective active surface area of the at least one hydraulic unit of the at least one first actuator.

Preferably, the ratio of the effective active areas corresponds to the ratio of the accumulated forces. This causes the pressure of the hydraulic oil in the hydraulic units of the first and second actuators to move in a similar range.

Then, all hydraulic units of all actuators may be designed for the same maximum pressure. At pressures higher than the maximum pressure, the hydraulic unit is subject to unsealing or rupture. The same applies to the piping and all other components. It is therefore advantageous that the achieved and achievable pressures in the various components move within similar ranges.

The actuator is designed with a bellows as a hydraulic unit (instead of e.g. a common hydraulic cylinder) also for a high tightness of the hydraulic system, since no through-going hole for a piston rod or the like is needed, on the sealing of which leakage may always occur as well.

The spring as an accumulator is advantageous because of its substantially linear characteristics and simple construction and operation.

It is particularly preferred that the ratio of the effective active areas of the hydraulic bellows of the second and first actuators is between 2:1 and 4:1, for example 3: 1. Especially when using the same bellows one will use more bellows in the second actuator.

The connection of the actuator to the valve rod, which is not only fixed but also single-sided, can be achieved particularly advantageously by means of a thrust disk. The unilateral connection of the second actuator to the valve stem can then be obtained by a stop able to transmit the movement of the thrust disc to the valve stem when the thrust disc of the second actuator moves towards the safety position.

Preferably, the accumulators of the actuators push the thrust disk towards the safety position of the valve in the event of a pressure relief, and the hydraulic units of the actuators push the thrust disk, when filled with hydraulic oil, against the action of the accumulators in the direction away from the safety position.

A very compact construction can be achieved when each actuator has as many hydraulic units and springs as the accumulator and the thrust disc is formed in such a way that the hydraulic units are inside the springs. However, this embodiment has the disadvantage that the thrust disk must have a complex shape which is obviously not disk-shaped. For example, the thrust disc may have a cylindrical protuberance at a position corresponding to the inside of the spring, which protrudes into the spring and is fitted with a hydraulic unit.

In an advantageous embodiment of the control valve, at least one first actuator for adjusting the position of the valve core part is arranged above the at least one second actuator.

It is particularly advantageous if a rigid housing part is provided between the at least one first actuator and the at least one second actuator, which housing part receives the force of the at least one energy store of the at least one second actuator. The housing part can then be, for example, disk-shaped with a central through-opening for the valve rod.

In this way, a very advantageous control of the hydraulic electric drive, i.e. by means of electric pulses, is achieved, the hydraulic pump being a fully encapsulated pulse pump. In such pumps, there is an armature as a piston inside, which is moved by a magnetic field and the fluid to be pumped is cyclically compressed. Such a pump is also compatible with digital control devices. It also has the advantage of a very high tightness, since no through-going hole of the movable part is needed, but only a fluid port. Thus, unnecessary losses in the hydraulic system can be avoided.

Preferably, the pulse pump is a piston pump with an electromagnetic stroke system.

It is particularly preferred that the pulse pump has a return spring for the pump piston in its interior.

The pulse pump thus designed has a comparatively low power consumption and a simple, inexpensive construction in addition to a high degree of tightness.

When a two-position three-way valve selectively connects the hydraulic pump to the at least one first actuator or the at least one second actuator, the same pump can be used in a simple manner for pretensioning the at least one second actuator for a safety function or a fail-safe function, or for adjusting the valve position in normal operation by means of the first actuator. The switching between the hydraulic units to be filled with high-pressure hydraulic oil is thus performed in a simple and easily controllable manner.

In a preferred development of the invention, the hydraulic electric drive has a reservoir for hydraulic oil in the form of a bellows. Bellows have the advantage of a particular seal, since, unlike piston cylinders and the like, there is no need for a through-hole with a seal for the movable rod. Furthermore, the bellows is relatively sensitive to mechanical action from the outside. The embodiment in which a blow accumulator is used as the accumulator for hydraulic oil instead of the bellows is slightly less advantageous.

In particular, it is preferred that the reservoir bellows is pretensioned by means of a spring. This is used to achieve or approximately constantly maintain a certain base pressure level in the reservoir bellows.

A compact construction can be achieved in that the reservoir bellows is integrated into the drive mechanism housing.

For a safety function or failsafe function, such as a reliable functioning in the event of a power failure, it is advantageous if the safety valve is a normally open two-position two-way valve. That is, it is "always on" without a control signal.

Advantageously, a second two-position two-way valve of the normally open type is also provided, which on the one hand allows hydraulic oil to flow out of the hydraulic unit of the first actuator in the event of a fault condition and on the other hand is used to adjust the valve core position by means of the first actuator.

When a throttle valve limiting the hydraulic oil speed when exiting the hydraulic unit is provided between each two-position two-way valve and the corresponding hydraulic unit, the speed can be set to the closed position when adjusting the valve position or optimally when in the safety position in the fault state, so that an excessively hard impact of the valve cone on the valve seat can be prevented.

By means of an overpressure valve arranged in parallel with the second two-position two-way valve, damage or rupture of at least one hydraulic unit of the first actuator when moving into the safety position can be prevented in the event of a failure of the two-position two-way valve. That is, the accumulator of the second actuator must be sufficiently strong, perhaps also acting against at least the first hydraulic unit of the first actuator, to reach the closed position. If the second two-position two-way valve is not in the open state in the fault state as specified and allows hydraulic oil to flow out of the first hydraulic unit of the first actuator, the hydraulic unit can be damaged or broken when it is compressed, but it is filled with hydraulic oil. This is prevented by the overpressure valve, which is triggered at a pressure that is slightly higher than the maximum normal operating pressure of the first hydraulic unit of the first actuator. The latter is reached when the first hydraulic unit is maximally filled with hydraulic oil and the first reaction accumulator is maximally compressed.

In order to increase the availability at low temperatures, it is advantageous to use hydraulic fluids containing antifreeze additives instead of hydraulic oils with a limited temperature range of use.

If the bellows is used as a hydraulic unit, the design of the construction is simple when it is a bellows which is subjected to internal pressure.

If the bellows is used as a hydraulic unit, more load cycles can be obtained when the bellows is subjected to external pressure.

Drawings

Additional details and features will be apparent from the following description of preferred embodiments taken in conjunction with the accompanying drawings. In this case, the respective features may be implemented individually per se or in combination with one another. The possible ways of accomplishing the task are not limited to the described embodiments. Thus, a range description, for example, always includes all non-claimed intermediate values and all conceivable sub-intervals.

An embodiment is schematically shown in the drawings. In the drawings, in which the same reference numbers indicate identical or functionally corresponding parts, there is shown in detail:

figure 1 shows a schematic cross-sectional view of a regulating valve of the present invention in a safety position;

FIG. 2 shows a schematic cross-sectional view of the regulator valve of FIG. 1 with the actuator spring pre-tensioned for a fail-safe or safety function in preparation for normal operation;

FIG. 3 shows a schematic cross-sectional view of the regulator valve of FIG. 1 or FIG. 2 during normal operation of the process; and

fig. 4 shows a schematic circuit diagram of the hydraulic electric drive mechanism of the regulating valve of the present invention.

Reference numerals

A 110 stem;

120 a thrust disc of the first actuator;

130 a thrust disc of a second actuator;

135 a shell member;

140 a stop or force transfer ring;

150 a bellows of the first actuator;

160 a bellows of a second actuator;

170 spring of the first actuator;

180 a spring of the second actuator;

190 a valve seat;

395 the valve cone;

405 a storage;

410 a spring for the accumulator;

415 a pulse pump;

420 two-position three-way valves;

425 a fail-safe bellows system of the second actuator;

430 a spring of the second actuator;

435 a modulating bellows system of the first actuator;

440 a spring of the first actuator;

445 check valves;

a check valve at 450 reservoir;

455 is a two-position two-way valve;

460 a throttle valve for a first actuator;

465 control means (electric);

470 two-position two-way safety valve;

475 throttle valve for second actuator;

480 overpressure valve.

Detailed Description

FIG. 1 shows a schematic view of a

A control valve according to the invention with the proposed hydraulic electric drive is shown in fig. 1. The valve stem 110 is axially movable by means of two thrust

discs

120, 130. The thrust disc 120 of the first actuator for adjustment is rigidly connected to the valve stem 110. The thrust disk 130 of the second fail-safe actuator is connected to the valve stem 110 via a force transmission ring or stop 140, so that the force transmission from the thrust disk 130 to the valve stem 110 is only possible in the direction to the safe position. The bellows 150,160 are located below the thrust disks 120,130, by means of which the thrust disks 120,130 can be moved upwards against the action of the

springs

170, 180. They sit above the thrust disks 120,130 and push the thrust disks 120,130 downward when the bellows 150,160 is empty. The spring 180 of the second fail-safe actuator is now supported on the housing part 135.

The bellows and spring system may be designed in the form of a set of bellows or springs individually or uniformly arranged around the valve stem 110. In the example shown, this is a set of three bellows or springs, only two of which are visible in each case, as determined by the sectional view.

A strong fail-safe spring 180 is responsible for the large closing force required. While the spring 170 provided for normal operation may be designed to be significantly weaker. In the closed position, the springs 170,180 urge the valve stem 110 into the valve seat 190. The valve seat force and thus the leakage value is determined by the sum of all spring forces in the closed position. In fig. 1, the regulating valve is in a safety position corresponding to the closed position. All of the bladders 150,160 are pressureless. The valve seat force is high due to the spring force of the fail-safe spring 180, and thus the leakage is small. The small force of the adjusting spring 170 is added to it and increases the valve seat force again by the portion.

FIG. 2

Fig. 2 shows a state at the time of preparation before normal operation. Here, the pressure in the bellows 160 of the second fail-safe actuator is first increased. To this end, hydraulic fluid is pumped into fail-safe bellows 160, so that it lifts the respective thrust disk 130 and compresses the respective spring 180 against housing part 135. The thrust disc 130 is thus lifted off the force transfer ring 140 and gives the valve stem 110 the possibility to move away from the safety position, in this case upwards. In this case, at least exactly as many strokes as are required for the subsequent course adjustment have to be performed. The large closing force in the valve seat 190 is now lost, since only the weaker spring 170 of the first (regulating) actuator pushes the valve stem 110 into the valve seat 190.

The pulse pump provided for pressurizing the hydraulic bellows can be designed such that it delivers enough power to achieve the required regulation speed of the bellows 150 of the first actuator. The active surface or effective cross section or working surface of fail-safe bellows 160 of the second actuator and thus the volume still to be filled is greater than the active area and volume of adjustment bellows 150 because of the greater force required. Preferably, the system is therefore designed such that the maximum pressure required is approximately the same size for all the bellows (the bellows of the first actuator 150 and the bellows of the second actuator 160). Therefore, the moving speed is reduced only when the fail-safe bellows 160 is pressurized in the case of using the same pump. This procedure accordingly requires more time, which is not a disadvantage in practice, since only few failsafe accidents occur. For example, a regulator valve that requires 5 seconds to move from the closed position to the open position during normal operation of the regulator may require 15 seconds of readiness (pressurization of the fail-safe bellows) before it is ready for use.

FIG. 3

The situation in normal operation of the process is shown in fig. 3. Fail-safe spring 180 is fully compressed by fail-safe bellows 160. They store the force required for a fault condition, e.g. due to a power outage. By controlling the pulse pump, the pressure within bellows 150 can be increased. Here, the valve stem 110 may be moved away from the closed position, here upward, in respective increments by several pulses of electrical current. In fig. 3, it will be seen that the valve cone 395 is lifted from the valve seat 190 into an open position which is meaningful for process adjustment. The pressure in the control bellows 150 can be reduced by an opening pulse acting on a two-position two-way valve associated with the first actuator for control. The valve rod 110 is then pressed downward by the adjusting spring 170 by a corresponding increment toward the closed position, i.e., here. This rapid pulse sequence may cause the valve stem 110 to move up and down approximately continuously as well.

FIG. 4

Figure 4 shows a schematic circuit diagram of a complete hydraulic electrically operated valve drive system. The complete hydraulic system is filled free of air with incompressible hydraulic oil or hydraulic fluid. A hermetically closed bellows is preferably used as the reservoir 405 for the fluid. It may be pre-tensioned with a spring 410 to reach a certain base pressure level or to maintain a certain base pressure level approximately constant.

The pulse pump 415 is constituted by an electromagnetic stroke magnet system. Whereby pressure pulses can be generated by rectangular control current pulses. Which bellows or which bellows should be pressurized is selected by a two-position three-way valve 420.

At the beginning, the fail-safe bellows system 425 of the second actuator is pressurized as a preparatory means of operation to pre-tension the safety spring 430 of the second actuator to make it ready for use. The first actuator's regulating bellows system 435 is then charged to the desired operating state against the corresponding spring 440. The power of the pulse pump 415 is designed with respect to the pressure and delivery volume for adjusting the

first actuators

435, 440. The early time for storing the fail-safe energy is tolerated for a longer time corresponding to a larger active area or larger volume of fail-safe bellows system 425.

Check valves 445 prevent backflow of hydraulic fluid after an increment of travel of the respective bellows system. A portion of the hydraulic fluid is replenished from the reservoir 405 after each pump pulse for the next pulse through a check valve 450 on the reservoir. For this purpose, the pulse pump 415 has a return spring (not shown) for a pump piston therein. The pulse pump 415 can always remain de-energized after a certain deflection of the bellows is reached. The respective position is always kept free of energy by the closed (reversing) valve (as is also the case in pneumatic drives). This applies not only to fail-safe bellows system 425, but also to adjustment bellows system 435.

For the downward adjustment, the two-position two-way valve 455 is switched by the control means 465. By means of a temporary pulse-like switching, a controlled increase of the downward stroke can be activated, while by means of a permanent switching a complete withdrawal is possible. The cross section of throttle 460 now determines the downward movement speed.

In the case of a power failure or on a corresponding command, the two-position two-

way valves

455, 470 are opened. The second two-position communication valve 470 is now used only as a safety valve for venting the fail-safe bellows system 425 of the second (fail-safe) actuator. A throttle 475 is also provided here for limiting the closing speed of the valve. If the

valves

455, 470 are of the preferably normally open type (normally open), opening may be automated in the event of a power failure. The fail-safe bellows system 425 and the regulating bellows 435 empty into the bellows-like reservoir 405 and the

springs

430, 440 press the valve cone into its valve seat (not shown here) via the valve stem.

As an additional safety measure, an overpressure valve 480 is provided. If the two-position two-way valve 455 fails and cannot be opened, a strong pressure on the still-filled adjustment bellows 435 occurs due to the fail-safe spring 430 pushing down by means of the thrust disk connected by the valve stem. The overpressure valve 480 vents it into the reservoir 405, thus preventing the rupture of the regulator bellows 435. The safety position is also ensured by the resulting pressure reduction if they are still to be broken.

The reservoir 405, which is advantageously bellows-like, can be integrated into the housing of the drive mechanism. The bellows advantageously has a base area that is greater than the sum of the base areas of all the other bellows. It will be achieved that the required stroke of the bellows can be rendered significantly smaller than the stroke of the actuator bellows. In this way, a long service life of the reservoir bellows and, in combination with the reservoir bellows spring 410, a relatively constant pressure within the reservoir can be achieved.

By setting the size (cross section) of the throttle valves 460,475, the speed can be optimally adjusted when adjusting the valve position up to the closed position or when occupying the safety position in a fault state. This is advantageous because in this way the valve cone 395 is prevented from hitting the valve seat 190 too hard. Furthermore, the regulation dynamics are optimized, in particular, down-regulated, thereby.

The bellows can be designed not only as a bellows that withstands internal pressure, but also as a bellows that withstands external pressure. A bellows subjected to external pressure generally reaches a greater number of load cycles. In particular, the bellows 150,435 used for adjustment can therefore preferably be designed as a bellows which is subjected to external pressure. In the example shown here, the structure of the bellows which is subjected to the internal pressure is specified for the sake of simplicity.

It is less advantageous but advantageously possible for at least two fail-

safe bellows systems

425, 435 to be arranged side by side in a plane in the housing instead of axially overlapping as described further above.

Instead of hydraulic oils, which have a limited range of temperature applications, especially at low temperatures, hydraulic fluids containing antifreeze additives can be used.

Glossary

Actuator

The actuators convert the electrical signals into mechanical movements or other physical parameters (such as pressure or temperature) and thus actively intervene in the working process. The actuator is therefore typically a drive member. In the present invention, an actuator is a combination of at least one accumulator, such as a spring or an air spring, and at least one hydraulic unit, with suitable control means. For example, a bellows or a cylinder can be used as the hydraulic unit. The accumulator and the hydraulic unit act in opposite directions, respectively, so that a controllable movement in both directions can be achieved.

Drive mechanism with bidirectional or unidirectional action

A drive mechanism acting in one direction is understood to mean a fluid drive (hydraulic or pneumatic) in which, for example, pressure is exerted by the working medium in the bellows or on the membrane or on the piston in the cylinder from only one side for driving. The opposite movement is for example performed by a spring or gravity. In contrast, in the case of a double-acting drive, the working medium is used for movement in both directions. Thus eliminating a return spring or similar mechanism.

Hydraulic electric driving mechanism

The hydraulic electric driving mechanism is an electric control hydraulic driving mechanism.

Hydraulic telescopic bag

The telescopic bag is a flexible pipe which can be folded in an accordion shape. The bellows can be mounted on mutually mechanically telescopic members so that they are, for example, protected from the outside or sealed from their environment. The hydraulic bellows here fulfills the same purpose as a hydraulic cylinder, but does not have a piston inside and therefore also does not have a piston rod guided to move to the outside by means of a seal.

Hydraulic unit

A hydraulic unit refers to a component which is used in a hydraulic system and which, when filled with hydraulic oil, causes a movement of one component, generally in such a way that the hydraulic unit extends.

Thrust disc

In the present invention, the thrust disk is a disk-shaped member which bears and possibly transmits a force. A thrust disc may be used, for example, to connect a spring and/or a hydraulic bellows to the valve stem. The connection need not be rigid-the thrust disc may for example be movably mounted on the rod.

Fault state

The fault state is a state which is different from the normal state or the control state, i.e., is disturbed. It may be triggered by an instruction (e.g., a dispatch station) or automatically, typically due to a power outage. In the regulating valve, the valve core part itself then necessarily assumes the safety position without further control. This is most commonly referred to as valve closure.

Change-over valve, n position m way valve

Reversing valves are used in fluid technology to open or close a path for a working medium (for example compressed air or hydraulic oil) or to change the direction of flow. The directional valve is described in terms of a number of ports (m) and a number of on-off positions (n). A two-position three-way valve, for example, has three ports and two on-off positions.

Effective active area of hydraulic unit

The effective active surface of the hydraulic unit is the cross-sectional area fraction according to the formula F ═ p × a_wirkContributing to the resulting force. This share is generally really smaller than the maximum cross-sectional area because of the accordion-like design of the bellows.

Citations

DE102014019574B3

WO2012/073172A1

EP77596A1

Claims

1. A regulating valve with a hydraulic electric driving mechanism is characterized in that,

wherein the regulator valve has a valve stem (110) that actuates a core member;

wherein the valve stem is driven by a drive mechanism acting unidirectionally;

wherein the single acting drive mechanism has at least two actuators;

wherein at least one first actuator has at least one first hydraulic unit and at least one first reaction accumulator and is fixedly connected to the valve stem (110) and is used for adjusting the position of the core member;

wherein the hydraulic electric driving mechanism is provided with a hydraulic pump for pumping hydraulic oil;

wherein the hydraulic pump is designed to be able to fill the hydraulic units of the at least two actuators with hydraulic oil against the respective reaction accumulators;

wherein the at least one second actuator has at least one second hydraulic unit and at least one second reaction accumulator, the common accumulated energy of which is greater than the common accumulated energy of the at least one first reaction accumulator;

wherein the second actuator is connected to the valve stem such that the valve stem is entrained when the second actuator performs a movement towards a safety position; and

when the second actuator performs a movement in the opposite direction, the valve stem is not actively moved;

wherein at least one second hydraulic unit of the second actuator is connected to a relief valve, which, in the event of a fault condition, causes the hydraulic oil to flow out of the second hydraulic unit.

2. The control valve with an electric hydraulic drive according to claim 1, characterized in that each hydraulic unit has an effective active area, the effective active area of the at least one second hydraulic unit of the at least one second actuator being larger than the effective active area of the at least one first hydraulic unit of the at least one first actuator.

3. The regulator valve with an electrohydraulic drive mechanism of claim 2 wherein said ratio of effective areas corresponds to a ratio of accumulated forces.

4. A regulating valve with an electrically operated hydraulic drive according to claim 2 or 3, characterized in that all hydraulic units of all actuators are designed for the same maximum pressure.

5. The regulator valve with an electric hydraulic drive according to claim 1, wherein the at least one second hydraulic unit and the at least one second hydraulic unit comprise bellows.

6. The regulator valve with an electrohydraulic actuator of claim 1 wherein said at least one first reaction accumulator and said at least one second reaction accumulator have springs.

7. The control valve with an electrohydraulic drive according to claim 2, characterized in that the ratio of said effective areas is between 2:1 and 4: 1.

8. The control valve with an electric hydraulic drive according to claim 1, characterized in that each actuator is connected to the valve stem (110) by means of a thrust disc (120, 130).

9. The control valve with an electrohydraulic drive mechanism of claim 8,

said at least one first reaction accumulator of said at least one first actuator and said at least one second reaction accumulator of said at least one second actuator urge said thrust disc (120,130) towards said safety position of said valve in the event of pressure relief, and

the at least one first hydraulic unit (150,435) of the at least one first actuator and the at least one second hydraulic unit (160,425) of the at least one second actuator, when filled with hydraulic oil, urge the thrust discs (120,130) in a direction away from the safety position against the at least one first and second reaction accumulators.

10. The control valve with an electrohydraulic drive according to claim 8 or 9, characterized in that,

said at least one first and said at least one second reaction accumulators are springs,

each actuator having as many hydraulic units and springs, an

The thrust disc (120,130) is formed in such a way that the at least one first hydraulic unit and the at least one second hydraulic unit are located within the spring.

11. The regulator valve with an electric hydraulic drive according to claim 1, wherein the at least one first actuator for adjusting the position of the spool member is disposed above the at least one second actuator.

12. The control valve with an electrohydraulic drive according to claim 11, characterized in that a stationary housing part (135) is provided between the at least one first actuator and the at least one second actuator, said housing part being subjected to the force of the at least one second reaction accumulator of the at least one second actuator.

13. The control valve with an electrically operated hydraulic drive as claimed in claim 1, characterized in that the hydraulic pump is a fully encapsulated pulse pump (415).

14. The regulating valve with an electrohydraulic drive according to claim 13, wherein the pulse pump is a piston pump with an electromagnetic stroke system.

15. The regulating valve with an electrohydraulic drive according to claim 14, wherein the pulse pump has a return spring for the pump piston in its interior.

16. The regulating valve with an electric hydraulic drive according to claim 1, characterized in that a two-position three-way valve (420) selectively connects the hydraulic pump to the at least one first actuator or the at least one second actuator.

17. The control valve according to claim 1, characterized in that the hydraulic motor drive has a bellows-like reservoir (405) for the hydraulic oil.

18. The control valve with an electrohydraulic drive according to claim 17, characterized in that the bellows-like reservoir is prestressed by means of a spring (410).

19. The regulating valve with an electrohydraulic drive according to claim 17 or 18, characterized in that the reservoir in the form of a bellows is integrated into the housing of the drive.

20. The regulator valve with hydraulic electric actuator according to claim 1, wherein the relief valve is a two-position two-way valve of a normally open type.

21. The control valve with an electrohydraulic drive mechanism of claim 20,

a second two-position two-way valve of a normally open type is arranged,

wherein the second two-position two-way valve on the one hand allows the hydraulic oil to flow out of the first hydraulic unit of the first actuator in the event of a fault condition and on the other hand is adapted to adjust the position of the valve core piece by means of the first actuator.

22. The regulating valve with an electrohydraulic drive according to claim 21,

a throttle (460,475) is provided between each two-position two-way valve and the corresponding at least one first hydraulic unit and the at least one second hydraulic unit, wherein the throttle limits the speed of the hydraulic oil when flowing out of the hydraulic units.

23. The control valve with an electrically operated hydraulic drive as claimed in claim 22, characterized in that an overpressure valve (480) is provided in parallel with the second two-position two-way valve for preventing at least one first hydraulic unit of the first actuator from being damaged when the second two-position two-way valve is moved into the safety position in the event of a malfunction.

24. The regulator valve according to claim 1, wherein the hydraulic motor drive uses a hydraulic fluid containing an antifreeze additive.

25. The regulator valve with an electrohydraulic actuator of claim 5 wherein said bellows is subject to an internal pressure.

26. The regulator valve with an electrohydraulic actuator of claim 5 wherein said bellows is subject to external pressure.