DE102016222242B4 - Valve assembly and thus equipped fluid operated actuator - Google Patents

Abstract

Valve arrangement (1), with at least one valve unit (15), the one in the context of an axial switching movement (24) between a two valve channels (22, 23) fluid-tightly separated from each other closing position and one of the two valve channels (22, 23) releasing a maximum Overflow cross-section fluidly interconnecting open position reversible valve spool (25), which is associated with a detection device (63) having a with the valve spool (25) movement-coupled actuating means (64) and one on the actuating means (64) responsive, on a valve spool (25 ), the assignment between the actuating means (64) and the sensor means (66) is selected so that the sensor means (66) in the closed position of the valve spool (25) has a first operating state and in the open position of the valve spool (25) assumes a second operating state, dadurc h, characterized in that the valve slide (25) has an opening start position lying between the closed position and the open position, which initiates the opening process by releasing an overflow cross section starting from the closing position of the opening switching movement (24a) of the valve slide (25), the assignment between the actuating means (64) and the sensor means (66) is selected so that the sensor means (66) in the opening switching movement (24a) of the valve spool (25) after leaving the closed position and before reaching the opening start position in the second operating state.

Description

The invention relates to a valve arrangement having at least one valve unit which has a closing position that is fluid-tightly separated from one another in the course of an axial switchover movement and a valve slide which fluidically interconnects the two valve channels with the release of a maximum overflow cross-section, to which a detection device is assigned. the one comprising the valve spool motion-coupled actuating means and a responsive to the actuating means, on a valve spool receiving valve housing fixed sensor means, wherein the association between the actuating means and the sensor means is selected so that the sensor means in the closed position of the valve spool a first operating state and in the open position of the valve spool occupies a second operating state. The invention further relates to a fluid-actuated adjusting device equipped with such a valve arrangement.

A valve assembly of the aforementioned type is known from DE 10 2009 058 977 A1 known and serves as a barrier device for hydraulic cylinders. The known valve arrangement has a valve slide which can be positioned in two different switching positions, in which it separates two valve channels either taking a closed position from each other or fluidly connects to each other taking an open position. The valve spool carries a permanent magnet which can cooperate with a stationary Hall sensor to generate a position indicating a switching position of the valve spool can. In such valve arrangements, it is fundamentally difficult to arrange the permanent magnet and the Hall sensor so that the generated position signal also corresponds with certainty to the switching position to be detected. Manufacturing and assembly tolerances can have a negative effect on the switching accuracy. Thus, for example, critical operating situations may arise when the detection device detects a closed position of the valve spool, although the valve spool has already been moved into an open or partially open position.

To counter this problem, was in the DE 20 2016 102 944 U1 in connection with a hydraulic multi-way valve already proposed to provide two activatable by the same actuating means sensor means which respond alternately to different switching positions of a valve spool, wherein in each of two switching positions each activates a sensor means and at the same time the other sensor means is deactivated. The associated structural and control engineering structure is relatively large.

From the EP 1 580 476 B1 a fluid-operated adjusting device is known, which comprises a working device designed as an actuator, which is equipped with a valve arrangement. The valve assembly includes two valve units mounted directly on the actuator and provided with means to affect the fluidic actuation of the actuator and to allow pressure sensing or flow sensing. For pressure detection or flow detection, each valve unit is equipped with a suitable sensor. As means for fluid control, for example, a throttle device and / or a check valve and / or at least one control valve and / or at least one manual override device are provided.

From the DE 10 2012 217 499 A1 a control device is known, which serves to control valve timing of an internal combustion engine. The controller includes a microcomputer that processes input information from various switches and sensors of the engine. Furthermore, the control device comprises a hydraulic circuit which is equipped with an electromagnetic directional control valve.

The DE 10 2010 043 259 A1 describes, in the context of a device for operating a locking mechanism, a method for detecting a malfunction of the device.

The invention has for its object to provide a safety-oriented valve arrangement, the operating state can be reliably monitored despite cost-effective design. Furthermore, a fluid-actuated adjusting device equipped with such a valve arrangement is to be provided.

To solve this problem is inventively provided in a valve arrangement of the type mentioned that the valve slide has a between the closed position and the open position opening start position, which initiates the opening process by starting releasing a Überströmquerschnittes starting from the closed position successful opening switching movement of the valve spool, said the assignment between the actuating means and the sensor means is selected so that the sensor means in the opening switching movement of the valve spool after leaving the closed position and before reaching the opening start position changes to the second operating state.

The invention is further achieved by a fluid-operated adjusting device, which contains an actuatable by controlled fluid loading, designed as an actuator work equipment, which is equipped with a valve assembly corresponding to the above, at least one valve unit is attached to the actuator.

The valve assembly according to the invention has at least one valve unit with a selectively positionable in a closed position or in an open position valve slide. When switching between these two switching positions of the valve slide performs a switching movement, which is depending on the switching direction an opening switching movement or a closing switching movement. In the closed position, two valve channels of the valve unit are fluid-tightly separated from each other by the valve spool to prevent fluid flow. In connection with a fluid-operated adjusting device, a fluid volume located in an actuator can thereby be locked. In the open position of the valve slide, a maximum overflow cross-section between the two valve channels is released, which allows fluid flow with the greatest possible flow rate. A detection device of the valve unit is able to determine whether the valve spool is in the closed position or in the open position. Each of these two switching positions of the valve spool is characteristic for one of two possible operating states of a sensor means, which can be activated or deactivated by an actuating means engaging in the movement of the valve spool, depending on the instantaneous relative position. An essential aspect of the invention is that between the actuating means and the sensor means such an assignment is selected, that the sensor means, when the valve spool is moved from the closed position to the open position, from its in the closed position of the valve spool occupied first operating state in the on the taking of the open position indicative second operating state changes, while the valve spool actually occupies a closed position. The actual opening process until reaching the maximum overflow cross-section providing open position is a continuous process that takes place during a certain stroke of the valve spool. The opening process begins at a position of the valve slide designated as opening start position, an increasing overflow cross-section being released until finally the open position is present. According to the invention the actuating means and the sensor means are arranged so that a change of the operating state of the sensor means from the first to the second operating state definitely occurs before reaching the opening start position. Such a design can be easily based on the known tolerances, so that can be ruled out with certainty that the sensor means occupies an indicative of the closed position operating state, although the valve spool already in the open position or in an adjoining the opening start position part-open position located. Regardless of existing tolerances, safe valve position monitoring of the valve slide is thus possible with the aid of the valve arrangement. Since the required circuitry complexity is low, the valve assembly can be realized inexpensively.

Advantageous developments of the invention will become apparent from the dependent claims.

Preferably, the association between the actuating means and the sensor means is designed so that in the opening switching movement, the change from the first operating position to the second operating position takes place when the valve spool has traveled only 40% to 80% of lying between the closed position and the opening start position path , In such a design, the monitoring function is subject to a particularly high safety range, which in particular even then allows a very reliable operation monitoring when the mutual association between the actuating means and the sensor means due to external circumstances such as temperature changes or wear undergoes certain changes.

An additional safety aspect can be realized in that the assignment between the actuating means and the sensor means is selected in such a way that the sensor means in the starting from the open position closing switching movement of the valve spool only after exceeding the opening start position from the second operating state in the first operating state replaced. In other words, therefore, the closed position is only detected during the closing process, if it is ensured with certainty that the valve spool has left each still a small overflow cross-section releasing position.

Depending on the relative position present between the actuating means and the sensor means, the sensor means is either activated or deactivated. Preferably, the valve arrangement is designed such that the first operating state of the sensor means is an activated state and the second operating state of the sensor means is a deactivated state.

It is provided in particular that the sensor means in the activated state outputs an electrical confirmation signal. Such an electrical confirmation signal can be used in many ways to to indicate the relevant operating status. Preferably, the valve unit is provided with a communication interface, at which the electrical confirmation signal can be tapped to supply it to an electronic control device and / or a display device. For example, the valve unit can have a signal means which is suitable for outputting a light signal and which lights up in the activated state of the sensor means and extinguishes in the deactivated state of the sensor means. Immediately on the valve unit existing optical signal means allow a particularly simple and assignment correct switching position monitoring.

As an actuating means, in particular a permanent magnet means is recommended. For example, can be provided as a permanent magnet means a compact permanent magnet magnetic body, which is integrated in the valve spool.

As sensor means in particular a Hall sensor is used. However, another type of sensor means can be used, for example a so-called reed switch.

In the valve unit, the valve spool expediently forms part of a shut-off valve which has a 2/2 valve function. In a simple embodiment of the valve arrangement, the valve unit as a whole forms a shut-off valve.

A structurally preferred embodiment of the valve arrangement provides that the valve slide extends axially displaceably in a valve chamber of the valve housing of the valve unit, wherein the valve chamber is divided by an annular, radially inwardly facing valve seat into two axially spaced valve chamber sections, each with one of communicate with both valve channels. The valve seat is formed for example by an annular body inserted into the valve chamber or directly from the peripheral boundary surface of the valve chamber. A longitudinal section of the valve slide is designed as an overflow section whose outside diameter is smaller than the inside diameter of the valve seat and which is positioned in the open position of the valve slide at the same axial height with the valve seat so that an axially continuous overflow cross-section is defined which defines the maximum overflow cross-section. Axially on both sides of the overflow is flanked by one each in comparison to the overflow a larger outer diameter having valve spool portion of the valve spool, wherein one of these two valve spool portions positioned in the closed position of the valve spool at the same axial height with the valve seat and thereby sealingly against the valve seat sealing portion forms. The opening start position is defined by the fact that an existing in the transition region between the sealing portion and the overflow annular control edge of the valve spool loses the sealing contact with the valve seat. From this point on, an increasing amount of release of the overflow cross section sets in, which has a maximum in the open position of the valve spool.

The valve spool is preferably piston-shaped. He has in particular a circular outer contour. The overflow section and the adjoining valve slide sections are contoured in particular in a circular-cylindrical manner. The permanent magnet means is expediently accommodated in one of the two valve slide sections adjoining the overflow section.

Preferably, the valve spool is biased by a spring means of the valve unit in its closed position. To cause the reciprocating switching movement, it is therefore only necessary to initiate an effective in the direction of the open position driving force either in the valve spool or away from the valve spool. Such a driving force can be applied mechanically, for example, but is preferably provided by a fluid force.

Expediently, the valve slide has an axially oriented drive surface, which delimits a drive space, in particular in the valve chamber, which can be acted upon by a drive fluid in a controlled manner to bring about the switching movement. Preferably, the valve housing is provided with a connection means to which a fluid line can be connected, through which the supply and removal of the drive fluid can take place. To this fluid line is conveniently connected to the supply and discharge of the drive fluid control valve connected, which is expediently also part of the valve assembly.

A supply connection is expediently located on the valve unit, which communicates with a first valve channel of the two valve channels and through which a working fluid to be controlled by the valve unit can be fed and discharged. This supply connection is expediently connected via a fluid line to a preferably arranged away from the valve unit control valve device which can control the supply and discharge of the drive fluid. The control valve device is preferably also a part of the valve arrangement.

The second valve channel of the two valve channels of the valve unit expediently communicates with a work connection located on the outside of the valve housing, which connects with one actuated implement fluidly connected or connected. This working device is, in particular, an actuator which can be actuated by means of fluid force and in particular by means of compressed air, in particular a fluid-operated working cylinder. The working connection is preferably provided with a fastening interface via which the valve unit can be mechanically fixed directly to the working device. In conjunction with a working cylinder can be realized in this way a particularly compact cylinder-valve combination.

In a preferred embodiment, the valve unit has a normally closed emergency ventilation valve, which communicates with one of the two valve channels, in particular with the aforementioned second valve channel. Operation of the emergency exhaust valve allows venting of the associated valve port and the entire volume connected thereto in an emergency, even when the valve spool is in the closed position. The emergency ventilation valve is designed in particular manually operated and has for this purpose, for example, a button. However, it may also be equipped for a remote control, in particular for a fluidic remote control by means of a remote release valve.

In an advantageous embodiment of the valve arrangement, the valve unit has a throttle check valve which is switched on in the course of one of the two valve channels, in particular in the aforementioned second valve channel. The check valve is designed so that it prevents fluid flow in the direction of the valve spool in the relevant valve channel and permits in the opposite direction. A flowing in the open position of the valve spool in the direction of the valve spool fluid is therefore forced to flow through the throttle valve, which causes a limitation of the flow rate, resulting in, for example, a reduced operating speed of a connected implement.

It is also advantageous if, connected to one of the two valve channels, in particular to the aforementioned second valve channel, a built-in valve unit pressure display device is connected. This pressure indicator is in particular designed so that it visualizes the presence of a prevailing in the associated valve port operating pressure. It has for this purpose in particular a spring-loaded visualization element which is displaceable relative to the valve housing and is displaced against the spring force in a pressure display position pending operating pressure.

The emergency ventilation valve, the throttle check valve and the pressure indicator may each be provided alone or in any combination.

A preferred embodiment of the fluid-operated adjusting device has a working device, which is designed as an actuator, which can be actuated by controlled fluid loading and which is in particular a fluidic and preferably pneumatically actuated working cylinder. The actuator is equipped with the valve assembly and in this context equipped with at least one valve unit of the valve assembly. In the actuator is preferably a double-acting cylinder, which has an internal working piston, which divides two working chambers from each other and is adjustable by controlled fluid loading of the two working chambers. Each of the working chambers can be controlled by its own fluid channel supplied with a working fluid, wherein at least one of these working channels, a valve unit of the valve assembly is connected. As a result, the controlled application of fluid required for the operation of the working cylinder can take place through the relevant valve unit. If a valve unit is connected to both working chambers, there is the advantageous possibility of immovably blocking the working piston by positioning the valve slides of both valve units in the closed position.

• 1 eine bevorzugte Ausführungsform einer fluidbetätigten Stellvorrichtung im Zusammenhang mit einer ebenfalls bevorzugten Ausführungsform der erfindungsgemäßen Ventilanordnung,
• 2 eine der beiden in 1 illustrierten Ventileinheiten in einem abgestuften Längsschnitt gemäß Schnittlinie II-II aus 1, wobei der Ventilschieber bei Einnahme seiner Schließstellung gezeigt ist,
• 3 eine vom Ventilschieber bei der öffnenden Umschaltbewegung eingenommene Zwischenstellung zwischen der Schließstellung und der Offenstellung kurz vor Erreichen der Öffnungsbeginnstellung,
• 4 einen weiteren Querschnitt der Ventileinheit bei in die Offenstellung umgeschaltetem Ventilschieber,
• 5 eine perspektivische Schnittdarstellung der Ventileinheit in einer den 2 bis 4 entsprechenden Schnittebene und in der Offenstellung des Ventilschiebers, wobei ergänzend nicht ersichtliche interne Fluidkanäle schematisch angedeutet ist, und
• 6 ein Schaltbild der in die aus den anderen Figuren ersichtliche Ventileinheit integrierten Komponenten mit zugehöriger Verschaltung.

The invention will be explained in more detail with reference to the accompanying drawings. In this show:

• 1 a preferred embodiment of a fluid-operated adjusting device in connection with a likewise preferred embodiment of the valve arrangement according to the invention,
• 2 one of the two in 1 illustrated valve units in a stepped longitudinal section along section line II-II 1 wherein the valve spool is shown taking its closed position,
• 3 an intermediate position between the closed position and the open position, which is assumed by the valve slide during the opening switching movement, shortly before reaching the opening start position,
• 4 a further cross-section of the valve unit with switched in the open position valve spool,
• 5 a perspective sectional view of the valve unit in a 2 to 4 corresponding sectional plane and in the open position of the valve spool, where not complementary apparent internal fluid channels is indicated schematically, and
• 6 a circuit diagram of the integrated in the apparent from the other figures valve unit components with associated interconnection.

In the 1 is a preferred embodiment of a total reference numeral 1 designated valve assembly illustrated. The valve arrangement 1 is at a likewise in 1 illustrated preferred application with a controlled by fluid actuation work implement 2 combined, which in particular is a pneumatically actuable actuator 2a is. Together define the valve assembly 1 and the implement 2 a fluid operated actuator 3 ,

The actuator 2a has an actuator housing 4 in which a drive piston 5 is received linearly movable, with a front side of the actuator housing 4 outstanding piston rod 6 connected is. The drive piston 5 divides the interior of the actuator housing 4 axially in two drive chambers 7 . 8th , each with its own fluid channel 12 . 13 communicate with one through the valve assembly 1 concealed connection opening 12a . 12b to a lateral outer surface 14 of the actuator housing 4 opens. The valve arrangement 1 is at these two connection openings 12a . 12b connected and allows a coordinated controlled fluid loading of the two drive chambers 7 . 8th to the drive piston 5 including the attached piston rod 6 to move back and forth linearly and to position in desired positions as required. At the piston rod 6 can be fixed an unspecified external component, such as a machine component, by the actuator 2a moved and / or positioned.

The valve arrangement 1 contains at least one preferably designed as a unit manageable unit designed valve unit 15 , Preferably, the valve arrangement comprises 1 two valve units 15 , which applies to the embodiment. Because the two valve units 15 By way of example, have an identical structure, the further description of one of these two valve units 15 orientate.

The valve unit 15 is preferred for direct mounting on a working device 2 , in particular an actuator 2a , educated. An example is the valve unit 15 in the area of a connection opening 12a . 12b on the lateral outer surface 14 of the actuator housing 4 assembled. The valve unit 15 has a fastening interface formed, for example, as a screw-in socket 16 with which it is used for fixing to the actuator housing 4 in an internal thread of the associated connection opening 12a . 12b can be screwed. The 1 shows the screwed state.

The valve unit 15 has a valve body 17 that of a valve duct system 18 is interspersed. To this valve channel system 18 include a first valve channel 22 and a second valve channel 23 , The valve unit 15 contains one in the context of a direction indicated by a double arrow linear switching movement 24 between one out 2 apparent closing position and one off 4 and 5 apparent open position reversible valve spool 25 which is in the connection between the two valve channels 22 . 23 is turned on and in the closed position the fluid connection between the two valve channels 22 . 23 interrupts and releases in the open position. In the open position of the valve spool 25 is the hereinafter referred to as working fluid flowing fluid a maximum overflow for the passage between the two valve channels 22 . 23 to disposal.

The valve spool 25 is expediently part of a 2/2-valve function having shut-off valve 26 the valve unit 15 , Exemplary has the valve unit 15 even more functional components, which will be discussed later. In an unillustrated simple embodiment, the valve unit is 15 in total as a shut-off valve 26 educated.

The valve slide, which preferably has a longitudinal extent 25 is in one inside the valve body 17 trained elongated valve chamber 27 recorded linearly displaceable. The switching movement 24 is in the axial direction of the common longitudinal axis 28 of the valve spool 25 and the valve chamber 27 oriented.

In the valve chamber 27 is located with respect to the valve body 17 fixed annular valve seat 32 that is concentric with the longitudinal axis 28 arranged and oriented radially inward. Exemplary is the valve seat 32 from one in the valve chamber 27 fixed rubber-elastic sealing ring 33 educated. The valve seat 32 divides the valve chamber 27 in one constantly with the first valve channel 22 connected first valve chamber portion 34 and one constantly with the second valve channel 23 connected second valve chamber portion 35 ,

The first valve channel 22 leads to an outside of the valve body 17 arranged fluid connection, for better distinction as a supply connection 36 is designated. This supply connection 36 is in the preferred actuator 3 via an only schematically indicated fluid line 39 with an external control valve device 37 connected. The same is for example designed as a 4/2-way valve and depends on her Switch position capable of working fluid in the supply port 36 or from the supply connection 36 returning working fluid to the atmosphere. The control valve device 37 can also have a different valve functionality.

The second valve channel 23 Conveniently leads to a likewise on an outer side of the valve housing 17 located further fluid connection, the better distinction as a working connection 38 is designated. The work connection 38 is with the mounting interface 16 combined so that he is in on the work tool 2 assembled state with one of the connection openings 12a . 12b of the working device 2 communicates, whereby a fluid connection between the second valve channel 23 and one of the working chambers 7 . 8th of the actuator 2a is made.

In the embodiment, both valve units 15 with their supply connection 36 to the control valve device 37 connected. Thus, according to the current switching position of the control valve device 37 the two working chambers 7 . 8th of the actuator 2a alternately counteracted with working fluid or pressure relieved to the drive piston 5 to move in one or the other axial direction. However, a prerequisite is that the valve spool 25 every valve unit 15 is in its open position.

By the two valve spools 25 be positioned in its closed position, the second valve channel can be 23 including the working chamber communicating with him 7 or 8th from the first valve channel 22 disconnect, which has the consequence that in the second valve channel 23 and the associated working chamber 7 . 8th contained pressure medium is locked. This is the drive piston 5 prevented from linear motion. With the help of the valve units 15 Thus, a safety aspect can be realized that under certain circumstances, for example in the event of a power failure, the current operating state of the actuator 2a is frozen and no unwanted movements occur.

Preferably, the valve unit 15 with a spring device 42 equipped, through which the valve slide 25 is biased in a basic position, which is preferably and according to the embodiment is the closed position. The spring device 42 is especially within the valve chamber 27 in to the valve spool 25 housed coaxial arrangement, wherein they are axially on the one hand on the valve spool 25 and on the other hand on an end-side end wall of the valve chamber 27 supported.

The valve spool 25 is displaceable by imposition of a illustrated by an arrow driving force FA from the presence of non-existing driving force FA closed position in the open position. The thereby occurring switching movement 24 be for better distinction as an opening switching movement 24a designated. The opening switching movement 24a ends upon reaching the open position, which is defined by the fact that the valve spool 25 according to 4 and 5 on a respect to the valve housing 17 stationary first stop surface 43a incident. A removal of the driving force FA has the consequence that the valve spool 25 in the context of an opening switching movement 24a opposite closing switching movement 24b into the basic position, so exemplarily the closed position, returns. The latter is according to 2 defined by the fact that the valve spool 25 at a respect to the first stop surface 43a oppositely oriented second abutment surface 43b of the valve housing 17 comes to the plant.

The driving force FA is in principle arbitrarily generated. It may be, for example, an electromechanical or an electromagnetic driving force. Preferably, the valve unit 15 However, designed so that the valve spool 25 can be switched by means of a fluidic drive force FA, which applies to the embodiment. In this context, the valve spool has 25 via an axially oriented drive surface 44 , which has the same orientation as the closing switching movement 24b , The drive surface 44 preferably limits one from an end portion of the valve chamber 27 formed drive space 45 , with one outside the valve body 17 accessible connection means 46 communicates to the one in 1 schematically indicated fluid line 47 can be connected, for better distinction as a control fluid line 47 is designated.

The control fluid line 47 provides a fluid connection between the respective valve unit 15 and one preferably also to the valve assembly 1 belonging to the valve unit 15 externally and separately arranged control valve 48 depending on its switching position provides the opportunity in the associated drive space 45 to feed a control fluid generating the fluidic driving force FA or the drive space 45 to vent so that the driving force FA is eliminated.

The control valve device is preferred 37 and the two control valves 48 the exemplary actuator 3 of electrically operable type and to an electronic control device 52 connected, which expediently also to the fluid-operated actuator 3 belongs. By the electronic control device 52 let the Operating states of the control valve device 37 and the two control valves 48 specify in an application-specific coordinated manner.

In a preferred embodiment, which corresponds to the embodiment, is the valve spool 25 designed as a spool having a plurality of successive lengths, including two axially spaced first and second valve spool portions 54 . 55 located as well as an interposed, for better distinction as an overflow section 53 designated third valve spool portion.

In the closed position of the valve spool 25 is the overflow section 53 over its entire length in the first valve chamber section 34 , At the same time, the first valve spool section passes through 54 the annular valve seat 32 and extends in each of the two valve chamber sections 34 . 35 , The second valve spool section 55 passes through the first valve chamber section 34 on the valve seat 32 axially opposite side limiting annular sealing surface 56 , which preferably in the same way as the valve seat 32 from a rubber-elastic sealing ring 33 is defined.

The outer diameter of the first valve spool portion 54 is so to the inner diameter of the annular valve seat 32 adjusted that between the valve seat 32 and the longitudinal portion of the first valve spool portion extending therethrough 54 a sealing contact is present, the fluid connection between the two valve chamber sections 34 . 35 prevented. The first valve spool section 54 thus represents a sealing section 54a of the valve spool 25 ,

The outer diameter of the second valve spool portion 55 is on the inner diameter of the annular sealing surface 56 tuned so that there is a sealing contact between these two components, when the second valve spool portion 55 through the annular sealing surface 56 extends through. This is preferably independent of the switching position of the valve spool 25 always the case. This is a to the annular sealing surface 56 subsequent third valve chamber section 57 from the first valve chamber portion 34 separated fluid-tight.

The outer diameter of the overflow section 53 is smaller than the outer diameter of the two axially flanking valve spool portions 54 . 55 , Preferably, the outer diameter of the two valve spool portions 54 . 55 equal in size to each other. During the second valve spool portion 55 regardless of the switching position of the valve spool 25 constantly through the annular sealing surface 56 protrudes and with the annular sealing surface 56 is in sealing contact, lies in the first valve spool portion 54 only in the closed position of the valve spool 25 a sealing contact with the valve seat 32 in front. In the open position of the valve spool 25 whereas, the first valve spool section is 54 over its entire length into the second valve chamber section 55 displaced into it, at the same time the overflow section 53 at the same axial height with the annular valve seat 32 located. The open position is defined in particular such that the longitudinal center of the overflow section 53 in the same, to the longitudinal axis 28 right-angled radial plane is like the annular valve seat 32 ,

In the open position is between the valve seat 32 and the overflow section 53 an annular overflow gap 58 defined axially continuous between the two axially adjacent valve chamber sections 34 . 35 runs and the one maximum overflow cross section for the between the two valve chamber sections 34 . 35 overflowing working fluid pretends.

The first valve spool section 54 or sealing section 54a goes over an annular edge in the overflow section 53 over, which in the following also as control edge 62 is designated. The control edge 62 is essentially on the diameter of the sealing portion 54a in the transition region between this sealing section 54a and the overflow section 53 ,

When the valve spool 25 starting from the in 2 illustrated closed position an opening switching movement 24a performs, the sealing section slides 54a with its outer periphery on the valve seat surrounding it 32 while maintaining a sealing effect. The control edge approaches 62 to the valve seat 32 axially. The overflow gap 58 is closed as long as the sealing section 54a at the valve seat 32 is applied. An opening process begins when the sealing portion 54a axially out of the valve seat 32 exits, which is exemplified by the fact that the control edge 62 through the valve seat 32 has passed through and the sealing contact with the valve seat 32 loses. The case of the valve spool 25 assumed position is called opening opening position.

From the opening start position increases when continuing the opening switching movement 24a the between the valve seat 32 and the valve spool 25 approved overflow cross section. A fluid transfer between the two with the valve channels 22 . 23 communicating valve chamber sections 34 . 35 It starts immediately at the beginning of the opening process, wherein the flow rate increases in particular gradually until it reaches a maximum, when the open position according to 4 and 5 is reached and consequently the maximum overflow is released.

In the case of the closing movement starting from the open position 24b approaches the control edge 62 back to the valve seat 32 in particular, wherein the free overflow cross-section is gradually reduced and is finally closed when the control edge 32 in the valve seat 32 enters and comes into sealing contact with this. This position corresponds to the assumed in the initial opening position axial position of the valve spool.

The valve unit 15 is with a detection device 63 equipped with the switching position of the valve spool 25 monitor. The detection device 63 includes one with the valve spool 25 motion-coupled actuator 64 That's every movement of the valve spool 25 participate directly. Preferably, the actuating means 64 around a permanent magnet means 64a , which has permanent magnetic properties and constantly generates a permanent magnetic magnetic field.

Preferably, the actuating means 64 inside the valve spool 25 arranged, for example, in a region of the third valve chamber section 57 lying receiving chamber 65 of the valve spool 25 , In the permanent magnet means 64a it is preferably a simple permanent magnetic body, for example in the manner of a bar magnet. The permanent magnet means 64a is based on the axial direction of the longitudinal axis 28 in particular axially polarized, so that the north pole at one end face and the south pole at the other end face of the permanent magnet means 64a is present.

Another component of the detection device 63 is a sensor means fixed to the valve housing 66 , which is fixed to the valve body 17 is arranged, and preferably outside of the valve chamber 27 , The sensor means 66 is so on the actuator 64 matched that by the actuator 64 is contactless activated when the actuating means 64 near an internal detection substrate 67 of the sensor means 66 arrives.

The sensor means 66 is preferably of a kind whose detection substrate 67 Contactlessly responsive to a magnetic field. Conveniently, the sensor means 66 as a Hall sensor 66a formed, which applies to the embodiment.

actuating means 64 and sensor means 66 are in such an assignment in the valve unit 15 integrated that the sensor means 66 in the closed position of the valve spool 25 a first operating state and in the open position of the valve spool 25 assumes a different from the first operating state second operating state.

The first operating state of the sensor means 66 is in particular an activated state, which has the consequence that the sensor means outputs an electrical confirmation signal. This confirmation signal is, for example, in the external electronic control device 52 processable, the signal to the valve unit 15 can be connected. In this context, the valve unit 15 expediently with a communication interface accessible from the outside 68 equipped with it to the electronic control device 52 connectable or connected. A corresponding electrical connection is indicated at 69.

The communication interface 68 is expediently 17 on from the valve housing 17 leading out electrical conductors, for example, in a flexible cable 73 are realized. The communication interface 68 is about this electrical conductor or the electrical cable 73 , in particular in the interior of the valve housing 17 , electrically conductive with the sensor means 66 connected.

The communication interface 68 can also directly on the sensor means 66 be arranged, for example, at the following as the sensor housing 74 designated housing of the sensor means, in which also the detection substrate 67 is housed. Likewise, the communication interface 68 outside on the valve body 17 are located. In all cases, the communication interface 68 preferably realized in the form of a connector interface.

The sensor means 66 can in any way on the valve body 17 the valve unit 15 be fixed. Advantageous is a fixation, which ensures that the relative position of the sensor means 66 with respect to the valve housing 17 even with shocks can not change. Exemplary is the sensor means 66 for this purpose, form-fit in a valve housing 17 trained sensor receiving chamber 75 fixed so that its relative position with respect to the valve housing 17 fixed and unchangeable. The sensor receiving chamber is preferred 75 from a housing cover 76 of the valve housing 17 covered, so the sensor means 66 is sheltered from environmental influences.

The sensor receiving chamber 75 is expediently alongside the valve chamber 27 in the valve housing 17 educated.

That by the sensor means 66 An audible electrical acknowledgment signal may be used to indicate the operating condition of the sensor means 66 to generate visualizing light signal. The embodiment has a corresponding equipment by here the sensor means 66 with a signal means suitable for light output 77 equipped, which is excitable by the confirmation signal. The signal means 77 located in the embodiment in the region of a recess of the valve housing 17 , in particular of the housing cover 76 so that the user can easily see from the outside whether the signal means 77 lit or not. The signal means 77 Optionally, it may also include an unillustrated light guide which directs the generated light signal to an eye-catching location in the exterior of the valve unit 15 passes.

The valve unit is preferred 15 designed so that the sensor means 66 in which the closed position of the valve spool 25 detected detecting the first operating state and in which the open position of the valve spool 25 Detective second operating state is disabled. In the activated state, the output of the electrical acknowledgment signal, which is not present in the deactivated state takes place.

The actuating means 64 and the sensor means 66 are arranged in such an association that the sensor means 66 at the opening switching movement 24a of the valve spool 25 changes from the hitherto existing first operating state to the second operating state before reaching the opening start position explained above. In the embodiment, this means that in the closed position of the valve spool 25 activated sensor means 66 when taking place from the closed position switching into the open position already in an intermediate position of the valve spool 25 is switched to the deactivated state, in the actually still the closed position of the valve spool 25 is present. Such an intermediate position, also referred to below as the operating state change position, is in 3 illustrated.

Preferably, this is a vote of the relative position between the actuating means 64 and the sensor means 66 before, that of the valve spool 25 Between the closed position and the operating state change position traveled stroke is in a range of 40% to 80% of the stroke, the valve spool 25 travels from the closed position to the opening start position. As a result, any tolerance influences with the greatest possible certainty can be excluded, without the usability of the detection device 63 to impair.

It is furthermore advantageous if the association between the actuating means 64 and the sensor means 66 is set up so that the sensor means 66 at the beginning in the open position closing switching movement 24b of the valve spool 25 only then changes from the second operating state corresponding to the open position into the first operating state corresponding to the closed position, after the valve slide 25 the opening start position has exceeded, that is more precisely one of the opening start position corresponding position.

Preferably, the design is such that the change of the operating state from the first operating state to the second operating state in the same operating state change position of the valve spool 25 takes place, in the reverse direction of movement of the valve spool 25 the change takes place between the second operating position in the first operating position.

The valve unit 15 can be optional with an emergency ventilation valve 81 be equipped. This emergency ventilation valve 81 is in the course of a via a vent 82 to the atmosphere ausmündenden emergency ventilation duct 83 turned on, that of the second valve channel 23 branches off and preferably in the interior of the valve housing 17 runs. By means of an actuating device 84 , which is designed in particular as a manual override, can be the emergency ventilation valve 81 if necessary from a normally the emergency ventilation duct 83 Shut-off closed position in a fluid passage through the emergency ventilation duct 83 switch over by releasing venting position. This allows venting of the second valve channel 23 and the attached implement 2 , in particular one of the connected working chambers 7 . 8th when the valve spool 25 the shut-off valve 26 the closed position occupies.

Also optional, the valve unit 15 with an integrated pressure indicator 85 be equipped. The same is at the second valve channel 23 connected, in particular via a suitable branch channel 86 , so that at her constantly in the second valve channel 23 prevailing fluid pressure is present. As a result, it can be seen, in particular, whether the shut-off valve is in the closed position 26 in the second valve channel 23 a fluid pressure is present or not.

The pressure indicator 85 is in particular designed so that it has a movable visualization element 87 which can change its position depending on the pressure. The visualization element 87 For example, takes an unconfirmed basic position in the pressureless state of the second valve channel 23 from which it is displaced to an actuated display position when in the second valve channel 23 a certain pressure level is present.

In the course of the second valve channel 23 Optionally a throttle check valve 88 to be on. This throttle check valve 88 contains a combination of a throttle valve 88a and a check valve connected in parallel therewith 88b , wherein the check valve 88b is formed so that there is a fluid flow towards the shut-off valve 26 prevented and allowed in the opposite direction.

In this way, a at a corresponding operating state of the control valve device 37 in the first valve channel 22 fed working fluid the throttle valve 88a pass and unthrottled to the work connection 38 stream. Is the control valve device 37 in contrast to a pressure relief or venting of the first valve channel 22 switched, can from the to the second valve channel 23 connected working chamber 7 . 8th the working fluid contained therein are throttled discharged, wherein the throttle valve 88a is preferably made adjustable, so that the throttling intensity can be varied as needed. With the help of the throttle valve 88a can be with an actuator 2a the adjustment speed of the drive piston 5 to adjust.

The valve unit 15 is suitably with a mounting portion 89 equipped with the mounting interface 16 and the work connection 38 having. The optional throttle check valve 88 is expediently in this attachment section 89 integrated.

The valve spool 25 is preferably located in a side of the mounting portion 89 protruding cuboidal functional section 93 the valve unit 15 , The functional section is preferred 93 with respect to the attachment section 89 pivotable and thus variably mountable in different orientations. The functional section 93 in particular has a rectangular cross section with a greater width than height.

Claims (19)

Valve arrangement (1), with at least one valve unit (15), the one in the context of an axial switching movement (24) between a two valve channels (22, 23) fluid-tightly separated from each other closing position and one of the two valve channels (22, 23) releasing a maximum Overflow cross-section fluidly interconnecting open position reversible valve spool (25), which is associated with a detection device (63) having a with the valve spool (25) movement-coupled actuating means (64) and one on the actuating means (64) responsive, on a valve spool (25 ), the assignment between the actuating means (64) and the sensor means (66) is selected so that the sensor means (66) in the closed position of the valve spool (25) has a first operating state and in the open position of the valve spool (25) assumes a second operating state, dadurc h, characterized in that the valve slide (25) has an opening start position lying between the closed position and the open position, which initiates the opening process by releasing an overflow cross section starting from the closing position of the opening switching movement (24a) of the valve slide (25), the assignment between the actuating means (64) and the sensor means (66) is selected so that the sensor means (66) in the opening switching movement (24a) of the valve spool (25) after leaving the closed position and before reaching the opening start position in the second operating state. Valve arrangement (1) according to Claim 1 , characterized in that the association between the actuating means (64) and the sensor means (66) is selected so that the change to the second operating position of the sensor means (66) takes place when the valve spool (25) at the opening switching movement (24a) 40% to 80% of the lying between the closed position and the opening start position path has covered. Valve arrangement (1) according to Claim 1 or 2 , characterized in that the association between the actuating means (64) and the sensor means (66) is selected so that the sensor means (66) at the outgoing from the open position closing switching movement (24b) of the valve spool (25) only after exceeding the opening start position changes from the second operating state to the first operating state. Valve arrangement (1) according to one of Claims 1 to 3 , characterized in that the one of the two operating states of the sensor means (66) is an activated state and the other operating state is a deactivated state. Valve arrangement (1) according to one of Claims 1 to 4 , characterized in that the sensor means (66) is activated in the first operating state and deactivated in the second operating state. Valve arrangement (1) according to Claim 4 or 5 , characterized in that the sensor means (66) outputs an electrical confirmation signal in the activated state, which can be tapped at a communication interface (68) of the valve unit (15) and / / or by means of which a light signal can be generated by a signal means (77) of the valve unit (15). Valve arrangement (1) according to one of Claims 1 to 6 , characterized in that the actuating means (64) is a permanent magnet means (64a) and / or that the sensor means (66) is a Hall sensor (66a). Valve arrangement (1) according to one of Claims 1 to 7 , characterized in that the valve slide (25) is part of a 2/2-valve function having shut-off valve (26) of the valve unit (15). Valve arrangement (1) according to one of Claims 1 to 8th , characterized in that the valve spool (25) extends axially displaceably in a valve chamber (27) of the valve housing (17) by an annular, radially inwardly facing valve seat (32) in two axially spaced and each with one of the two Valve channels (22, 23) connected valve chamber sections (34, 35) is divided, wherein the valve slide (25) has a comparison with the inner diameter of the valve seat (32) smaller outside diameter having overflow section (53) in the open position of the valve spool (25 ) is positioned at the same axial height with the valve seat (32) releasing the maximum overflow cross-section and is axially flanked on both sides by a valve slide portion (54, 55) having a larger outer diameter than the overflow portion (53), one of these two valve slide portions ( 54, 55) one in the closed position of the valve spool (25) at the same axial height with the valve seat (32) positioned and under sealing contact on the valve seat (32) radially adjacent sealing portion (54a), wherein the opening start position is defined by a sealing portion (54a) of the overflow (53 ) delimiting control edge (62) of the valve spool (25) loses the sealing contact with the valve seat (32). Valve arrangement (1) according to one of Claims 1 to 9 , characterized in that the valve slide (25) is biased by a spring means (42) of the valve unit (15) in its closed position. Valve arrangement (1) according to one of Claims 1 to 10 , characterized in that the valve slide (25) has an axially oriented drive surface (44) which limits a drive space (45), which is controlled to cause the switching movement (24) acted upon by a drive fluid. Valve arrangement (1) according to Claim 11 , characterized in that the valve housing (17) has a connection means (46), to which a supply and discharge of the drive fluid enabling fluid line can be connected. Valve arrangement (1) according to one of Claims 1 to 12 , characterized in that the valve unit (15) has a with the one, first of the two valve channels (22) communicating supply port (36) through which a of the valve unit (15) to be controlled working fluid can be supplied and discharged. Valve arrangement (1) according to Claim 13 , characterized in that the valve unit (15) has a with the other, second valve channel (23) communicating working port (38) via which it is fluidically connectable to a working device (2) to be actuated. Valve arrangement (1) according to Claim 14 , characterized in that the working port (38) via a mounting interface (16) for mechanically fixing the valve unit (15) on the working device (2) has. Valve arrangement (1) according to one of Claims 1 to 15 , characterized in that the valve unit (15) with one of the two valve channels (22, 23) communicating, normally closed Notentlüftungsventil (81), which is switchable in a respective valve channel (23) with the atmosphere connecting Notentlüftungsstellung. Valve arrangement (1) according to Claim 16 , characterized in that the emergency ventilation valve (81) is designed for manual operation. Valve arrangement (1) according to one of Claims 1 to 17 , characterized in that in one of the two valve channels (22, 23) in the valve unit (15) integrated throttle check valve (88) is turned on and / or that one of the two valve channels (22, 23) into the valve unit (15) integrated pressure indicator (85) is connected. Fluid-operated adjusting device (3), with an actuatable by controlled fluid loading, as an actuator (2 a) formed working device (2) with a valve assembly (1) according to one of Claims 1 to 18 is equipped, whose at least one valve unit (15) is attached to the actuator (2a).

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