Valve arrangement

Abstract

Valve arrangement (1; 81) with a control valve (2) designed to influence a working fluid flow and comprising a base body (9; 89) having an inlet port (5) and an outlet port (6, 7, 8), wherein the base body (9; 89) is penetrated by a fluid channel (51) extending between the inlet port (5) and the outlet port (6, 7, 8), wherein a valve seat (65) is arranged in the fluid channel (51) which is designed for a sealing connection of a valve element (30; 110) for blocking the fluid channel (51), wherein a valve element (30; 110) is arranged in the fluid channel (51) which comprises an actuator section (29; 109) and a sealing section (32), wherein the actuator section (29; 109) is arranged along a stroke (48) between a closed position and a Opening position sealing in an actuator recess (22) of the base body (9;89) is included and defines a variable-size working space (17) with the actuator recess (22), to which a supply channel (15) for supplying a control fluid flow into the actuator recess (22) and a discharge channel (16; 96) for discharging the control fluid flow from the actuator recess (22) are assigned, wherein the sealing section (32) is configured in the closed position for a sealing system on the valve seat (65) and in the open position for releasing the fluid channel (51), wherein the actuator section (29; 109) or the actuator recess (22) with the discharge channel (16; 96) forms a discharge valve, which is configured to influence the discharge of the control fluid flow into the discharge channel (16; 96) depending on a position of the valve element (30; 110) along the actuating path (48), characterized in that on an axially oriented end face (42) of the actuator section (29; 109) or on an axially oriented end face (20;100) of the actuator recess (22) a control projection (46; 126) is formed, wherein a profile of an outlet opening (19; 109) of the discharge channel (16; 96) which opens into the actuator recess (22) completely covers a profile of the control projection (46; 126).;

Description

[0001] The invention relates to a valve arrangement with a control valve which is designed to influence a working fluid flow and which comprises a base body on which an inlet connection and an outlet connection are formed, wherein the base body is penetrated by a fluid channel which extends between the inlet connection and the outlet connection, wherein a valve seat is arranged in the fluid channel which is designed for a sealing engagement of a valve member for blocking the fluid channel, wherein a valve member is arranged in the fluid channel which comprises an actuator section and a sealing section, wherein the actuator section is sealingly received in an actuator recess of the base body along a travel path between a closed position and an open position and defines a variable-size working space with the actuator recess,which is assigned a supply channel for supplying a control fluid flow into the actuator recess and a discharge channel for discharging the control fluid flow from the actuator recess, wherein the sealing section is designed in the closed position for a sealing engagement with the valve seat and in the open position for releasing the fluid channel, wherein the actuator section or the actuator recess forms a discharge valve with the discharge channel, which is designed to influence the discharge of the control fluid flow into the discharge channel depending on a position of the valve member along the actuating path.

[0002] Such valve arrangements, which are also referred to as pneumatically pilot-operated valves, are known from the applicant's product range. In this case, the control valve, also referred to as the main valve, is assigned a pilot valve which is designed to provide the control fluid flow to the control valve. Furthermore, the control valve has an adjustable fluid throttle which is designed to ensure, when the control fluid flow for the control valve is shut off by a throttled discharge of the control fluid, a return of the movable valve member accommodated in the control valve from a functional position, which can be defined either as a closed position or as an open position for the fluid channel, to a rest position, which can be defined either as an open position or a closed position.

[0003] DE 32 28 430 A1 discloses a continuously adjustable two-way installation valve, whose control element is loaded by a return spring located in a spring chamber and is pre-controlled by a hydraulic follow-up system, wherein the control element or a cylinder part connected therewith has a control chamber connected to the spring chamber, and wherein the control chamber can be connected to a supply line or a discharge line via a follow-up piston guided by the control element or the cylinder part within the control element or the cylinder part or on the jacket of the cylinder part via two control edges on the follow-up piston.

[0004] EP 2 924 327 A1 proposes a multi-way valve which contains a valve member which is movable in a valve chamber of a valve housing and which has a main body and an elastically deformable sealing plate which is fixed thereto, the sealing plate cooperating axially with at least one annular valve seat arranged opposite it on the valve housing, the sealing plate being enclosed on its radial outer circumferential surface by a support ring which is fixed exclusively to the sealing plate in order to avoid deformation during its contact with a valve seat as a result of the fluid forces acting on it.

[0005] The object of the invention is to provide a valve arrangement which enables particularly short switching times for the valve member of the control valve.

[0006] This object is achieved for a valve arrangement of the type mentioned at the outset with the features of claim 1.

[0007] It is known from the prior art to assign an adjustable throttle to the working chamber, also referred to as the upstream control chamber, which allows a throttled discharge of the control fluid from the actuator recess, regardless of the position of the valve member along the travel path. After the control fluid flow is shut off, the slow escape of the control fluid from the working chamber into the discharge channel enables the valve member, which is usually preloaded into the rest position by a spring, to return from the functional position to the rest position.

[0008] In the valve arrangement according to the invention, the discharge of the control fluid flow from the working chamber is dependent on the position of the valve member along the travel path. For example, the discharge valve is designed such that, in a functional position, which can correspond to a closed position or an open position for the valve member, a control fluid flow into the actuator recess corresponds to a volume flow of the control fluid flow out of the actuator recess, wherein a flow resistance for the outflow of the control fluid from the working chamber is slightly higher than a flow resistance for the inflow of the control fluid into the working chamber.This creates a balance between a force acting on the valve member by the pressurized control fluid and a restoring force directed toward the rest position, provided, for example, by a return spring, so that the valve member can be held in the functional position. For example, in the functional position, the discharge valve is fully open for the valve member, so that after the control fluid flow provided through the supply channel is shut off, a rapid return movement for the valve member from the functional position toward a rest position, which can correspond to an open position or a closed position for the valve member, can occur, since in the functional position, a maximum, unthrottled outflow of the control fluid through the discharge channel is ensured.Furthermore, the discharge valve is designed such that, as the valve member approaches the rest position, a reduction in the flow cross-section for the control fluid to be discharged from the working chamber occurs, since a throttling of the control fluid flow is provided, dependent on the valve member's travel. Due to the resulting increased flow resistance for the control fluid flowing from the working chamber into the discharge channel, the movement speed of the valve member is reduced as it approaches the rest position, and impact of the valve member against a stop within the base body that defines the rest position of the valve member is dampened or prevented.

[0009] Preferably, a separate design of the supply channel and the discharge channel is provided, as this enables rapid movement of the valve member toward the functional position, starting from the rest position of the valve member, in which the discharge channel is largely closed by the actuator section. The control fluid supplied into the working chamber in the rest position is initially used almost entirely to accelerate the valve member from the rest position to the functional position; only a small portion of the control fluid flows into the discharge channel, which is largely blocked by the discharge valve, at this time.Only when the valve element, starting from the rest position, has reached a design-specific position along the travel path during movement into the functional position does the discharge valve largely or completely open the discharge channel, allowing a significant portion of the control fluid supplied to the working chamber to flow into the discharge channel. At this point, however, the valve element has already reached a movement speed that ensures rapid reaching of the functional position despite the now increasing flow of control fluid through the discharge channel.

[0010] For example, it can be provided that the actuator section or the actuator recess and the discharge channel are coordinated with one another in such a way that the discharge valve formed thereby acts as a switching valve, i.e., a significant change in the cross-section of the discharge channel available for the discharge of control fluid occurs over a short section of the actuating travel. Preferably, a switching point for the discharge valve is selected such that a change in the discharge of the control fluid flow into the discharge channel occurs in the immediate vicinity of the rest position for the valve element. By shifting this switching point for the discharge valve towards the functional position, the valve element can reach the functional position more quickly from the rest position.This is of particular interest when it is acceptable that a movement of the valve member from the functional position requires a longer period of time to reach the rest position when the control fluid flow is switched off.

[0011] It is expedient if the discharge valve is designed to influence an inlet cross-section for the discharge channel between a release cross-section and a throttle cross-section, whereby the throttle cross-section amounts to at least 5 percent and a maximum of 25 percent of the release cross-section. The inlet cross-section for the discharge channel is the cross-section that is determined solely by the geometric design of the discharge channel's opening into the actuator recess and determines the flow resistance for the control fluid flow flowing out of the actuator recess. Depending on the design of the actuator section or the actuator recess, it can be provided that the inlet cross-section is fully released or possibly only partially released when the discharge valve is in the release position.It is crucial that the discharge valve does not completely block the inlet cross-section when the position of the valve element changes along the travel path, but rather that at least one throttle cross-section always remains open, through which control fluid can flow from the working chamber into the discharge channel at any time and in any position of the valve element. This throttle cross-section is dimensioned depending on the geometric design of the valve element and the actuator recess, as well as depending on the requirements of the control valve, in such a way that the valve element can move from the functional position to the rest position within a given period of time after the supply of control fluid is shut off.

[0012] In order to further enable the valve member to reach the functional position, it is provided that a flow resistance in the supply channel is selected to be smaller than a flow resistance in the discharge channel, whereby the flow resistance in the discharge channel is determined by the geometry of the discharge channel, by the inlet cross-section of the discharge channel and by the release cross-section dependent on the position of the valve member along the actuating travel. The geometric design of the supply channel and the discharge channel and the resulting flow resistances for the control fluid ensure that, during a supply of control fluid into the actuator recess, a pressure build-up takes place in the working chamber, which can bring the valve member from the rest position into the functional position and hold it there, even against a restoring force of a restoring means.If the discharge valve only releases the throttle cross-section due to the position of the valve member along the travel path, a rapid pressure buildup occurs in the working chamber. This may also result in an increased pressure level in the working chamber, since only a small portion of the supplied control fluid can flow out of the working chamber through the throttle cross-section. If, however, the discharge valve releases the release cross-section, the equilibrium described above is established between the inflow of control fluid, the outflow of control fluid, the resulting control fluid pressure in the working chamber, and the restoring force acting on the valve member.

[0013] Alternatively, it could be provided that the actuator section, depending on the position of the valve member along the travel path, partially covers an opening of the discharge channel, which opens into the actuator recess, in a throttle position. For example, it can be provided that the actuator section is designed as a working piston that is accommodated in a cylindrical, in particular circular-cylindrical, actuator recess for linear movement, and that a linear movement of the actuator section from the rest position to the functional position is induced by the provision of pressurized control fluid into the working chamber.With such a configuration of the actuator section and the actuator recess, one or more outlet openings can be provided on an inner circumferential surface of the actuator recess. These outlet openings are assigned to one or more discharge channels and are at least partially covered depending on the position of the actuator section of the valve member along the travel path. A outlet opening of a discharge channel configured in this way can also be considered a scavenging opening or overflow opening, as is known from the field of two-stroke engines.If a plurality of outlet openings are provided, these can be provided on the inner circumferential surface of the actuator recess or at least partially on an end face of the actuator recess, such that depending on the position of the valve element along the stroke path, a different number of the outlet openings is covered, while at least one outlet opening also remains open in the rest position of the valve element.

[0014] According to the invention, a control projection is formed on an axially aligned end face of the actuator section or on an axially aligned end face of the actuator recess, wherein a profile of an orifice of the discharge channel, which opens into the actuator recess, completely covers a profile of the control projection. The function of the control projection is to ensure, depending on a position of the valve member along the actuating path, in particular when the valve member approaches the rest position, at least partial, in particular extensive, blockage of the orifice of the discharge channel, thereby increasing the flow resistance for the control fluid for discharge from the actuator recess.To ensure the desired throttling effect for the discharge of the control fluid flow from the actuator recess through the outlet opening of the discharge channel into the discharge channel, the profile of the control projection, which can also be viewed as the cross-section of the control projection in a cross-sectional plane aligned perpendicular to the travel, is smaller than the profile of the outlet opening of the discharge channel in the same cross-sectional plane. Thus, a gap, particularly an annular gap, always remains open between the control projection and the inner surface of the outlet opening, even when the control projection is immersed in the outlet opening of the discharge channel.

[0015] In a further development of the invention, the control projection is formed on the axially aligned end face of the actuator section, and the discharge channel extends through the base body and connects the orifice to a discharge connection. With this configuration of the discharge valve, the control fluid flow is discharged independently of a working fluid flow that is to be controlled by the control valve. Such a design of the discharge valve is particularly interesting when the control fluid can be discharged easily, for example, into a vent channel for control compressed air or a return channel for control fluid.

[0016] In an alternative development of the invention, the control projection is formed on the axially aligned end face of the actuator recess, and the discharge channel extends through the valve body and connects the orifice to the fluid channel. This configuration of the discharge valve is particularly interesting when the control fluid flow is to be used as energy-efficiently as possible, for example, by supplying it together with a working fluid flow to an actuator associated with the control valve. If a pressure level for the control fluid flow is selected to be higher than a pressure level for the working fluid flow, the control fluid flow can flow through the valve member from the actuator recess into the fluid channel.If a pressure level of the control fluid flow is equal to or lower than a pressure level of the working fluid flow, a reliable discharge of the control fluid flow from the actuator recess can be ensured by suitable technical measures, in particular by radially feeding the control fluid flow at a constriction of a Venturi tube through which the working fluid flow flows.

[0017] In a further embodiment of the invention, it is provided that the discharge channel is tapered at least in sections, in particular in the shape of a cone section, starting from the orifice along the actuating path, and / or that the control projection is tapered at least in sections, in particular in the shape of a cone section, starting from the end face of the actuator section or from the end face of the actuator recess along the actuating path. This measure can influence the path-dependent change in the flow resistance for the discharge of control fluid from the actuator recess. For example, it can be provided that the discharge valve brings about a path-proportional change in the free cross-section of the discharge channel, starting from the release cross-section towards the throttle cross-section, as the valve member approaches the rest position.This allows a rapid approach to the rest position, initially starting from the functional position of the valve element, while as the distance to the rest position is increasingly reduced, an increasingly higher damping effect is caused by the discharge valve due to the reduction in the free cross section of the discharge channel, which in this case is proportional to the distance.

[0018] Preferably, the actuator section is configured such that the supply channel, the actuator recess, and the discharge channel are always fluidically connected to one another, regardless of the position of the valve member along the travel path. This ensures that the valve member is not prevented from reaching its rest position, which would be the case, for example, if the actuator section with the actuator recess enclosed a fluid volume that could not escape through the discharge channel.

[0019] It is advantageous if a pilot valve is assigned to the supply channel, which is designed to provide a control fluid flow to the supply channel and which is designed as a solenoid valve or piezo valve.

[0020] In a further embodiment of the invention, it is provided that the pilot valve is designed as a 2 / 2-way switching valve or as a 2 / 2-way proportional valve.

[0021] Advantageous embodiments of the invention are illustrated in the drawing. Fig. 1 a first embodiment of a valve arrangement with a schematically illustrated pilot valve and a detailed illustrated control valve in a closed position for the control valve, Fig. 2 the valve arrangement according to the Fig. 1 in an open position, Fig. 3 a detail view of a second embodiment of a valve arrangement in a closed position, and Fig. 4 the valve arrangement according to the Fig. 3 in an open position.

[0022] One in the Fig. The valve arrangement 1 shown in Figure 1 comprises a control valve 2 shown in detail, to which a schematically shown pilot valve 3 is assigned. According to the illustration of the Fig. 1, both the pilot valve 3 and the control valve 2 are in a closed position, so that neither a control fluid flow nor a working fluid flow is present. Due to the structural design of the control valve 2, the control valve 2 assumes the closed position without the presence of an external energy supply, in particular a control fluid flow, so that the closed position can also be referred to as the rest position.

[0023] Deviating from this, the presentation of the Fig. 2, the pilot valve 3 provides a control fluid flow to the control valve 2, whereby the latter is moved from the rest position according to the Fig. 1 into the open position, which in this case corresponds to a functional position, and in which the Fig. 2, and releases a valve seat described in more detail below, so that a working fluid flow can flow through the control valve 2, which is blocked in the rest position.

[0024] Purely by way of example, the pilot valve 3 is designed as an electromechanical 2 / 2-way valve, in particular as a solenoid valve or as a piezo valve, which, due to its only schematically shown design, has an extremely short switching time in the range of one millisecond for a change of its switching state between the Fig. 1 shown closed position and the one in Fig. 2 shown opening position. The pilot valve 3 is fluidically connected to the control valve 2 via a fluid line 4 shown only schematically, wherein the control valve 2 is controlled in a manner explained in more detail below by the provision of a control fluid flow from the pilot valve 3 from the rest position of the Fig. 1 into the functional position in the Fig. 2 can be transferred.

[0025] The control valve 2 comprises, purely by way of example, a supply connection 5, which can be connected to a fluid source (not shown in detail), in particular a compressed air source. Furthermore, the control valve 2 comprises, purely by way of example, a total of three working connections 6, 7, 8, to which at least one fluid consumer (not shown in detail) can be connected. Unused working connections 6, 7, 8 can be sealed fluid-tight, for example, by means of blind plugs (not shown).

[0026] By way of example, it is provided that the control valve 2 comprises a base body 9, for example, which is cuboid-shaped and is made in particular of metal or plastic, and which comprises a first base body section 10 and a second base body section 11, which lie against one another in a sealing manner in a parting plane 12 and are connected to one another by connecting means not shown in detail. By way of example, it is provided that the Fig. 1 and Fig. 2 left-hand main body section 10 is designed for the supply and discharge of the control fluid flow provided by the pilot valve 3, while the Fig. 1 and Fig. 2 The base body section 11 arranged on the right comprises the supply connection 5 and the working connections 6, 7 and 8.

[0027] Accordingly, a supply channel 15 and a discharge channel 16 are formed in the base body section 10, each exemplary as a bore or bore arrangement, which each open into a variable-sized working chamber 17. By way of example, it is provided that an opening 18 of the supply channel 15 and an opening 19 of the discharge channel 16 are each arranged on an end face 20 of a recess 21 formed in the base body section 10, wherein the end face 20 of the recess 21 partially delimits an actuator recess 22 which also encompasses the working chamber 17. The actuator recess 22 is further formed by a radially inwardly facing inner circumferential surface 23 of a valve bushing 24, which is inserted into the recess 21, which is purely exemplary in its circular cylindrical form, and is secured there in a manner not shown in detail, for example by force fit.

[0028] By way of example, it is provided that a circumferential groove 26 is formed on an outer circumferential surface 25 of the valve bushing 24, which groove is designed to receive a round cord sealing ring (O-ring) 27, which ensures a fluid-tight reception of the valve bushing 24 in the recess 21 by contact with an inner circumferential surface 28 of the base body section 10.

[0029] An actuator section 29 of a linearly movable valve member 30 is accommodated in the actuator recess 22. The valve member 30 is designed, purely by way of example, to be rotationally symmetrical to a central axis 31 and, in addition to the actuator section 29, includes a sealing section 32.

[0030] By way of example, it is provided that the actuator section 29 of the valve element 30 is formed by a carrier ring 33 which is connected to a rod-shaped basic body 34 of the valve element 30. For this purpose, a connection ring 35, which is formed in a conical section shape by way of example, is provided between the carrier ring 33 and the basic body 34 and is formed integrally with the carrier ring 33 and the basic body 34. The carrier ring 33 has a circumferential ring flange 36 which is provided on a first axially oriented end face 37 for axially supporting a shaft seal ring 38 which is provided in a sealing manner on the inner circumferential surface 23 of the valve bush 24. Furthermore, a second end face 39 of the ring flange 36 is formed as a contact surface for a return spring 40 assigned to the valve element 30.The shaft sealing ring 38 resting on the inner circumferential surface 23 of the valve bushing 24 is also sealingly fixed to an outer circumferential surface 41 of the carrier ring 33 and enables a linear movement of the valve member 30 relative to the valve bushing 24 and its inner circumferential surface 23.

[0031] By way of example, it is provided that the actuator section 29 is provided on an end face 42 facing away from the sealing section 32 with a groove-shaped recess 43 aligned in a circular ring coaxially with the central axis 31. An extension of the recess 43 in the radially outward direction is adapted to a position provided away from the central axis 31 for the supply channel 15 in such a way that control fluid provided through the supply channel 15 can flow unhindered into the working chamber 17. The recess 43 is further limited in the radially inward direction in such a way that a receiving section 44 is formed on the base body 34 of the valve member 30, which is purely exemplary and circularly cylindrical and aligned coaxially with the central axis 31.

[0032] The receiving section 44 is traversed purely by way of example by a bore 45 aligned coaxially with the central axis 31, in which a control pin 46, which serves as a control projection, is fixedly received. As can be seen from the illustration of the Fig. 1, the control pin 46 is designed to be inserted into the outlet opening 19 of the discharge channel 16. According to the detailed illustration of the Fig. 1, an outer diameter of the control pin 46 and an inner diameter of the orifice 19 are adapted to one another in such a way that a circularly profiled annular gap 47 is formed between the control pin 46 and the orifice 19. A cross-section of this annular gap 47 of a cross-sectional plane (not shown) aligned perpendicular to the central axis 31 is also referred to as a throttle cross-section. The annular gap 47 ensures in the rest position according to the Fig. 1 a fluidically communicating connection between the supply channel 15, the working chamber 17 and the discharge channel 16. This ensures that, regardless of a switching position of the pilot valve 3, control fluid can always flow out of the working chamber 17 through the discharge channel 16, whereby this permanent discharge of control fluid is also independent of the position of the valve member 30 along a travel path 48 aligned parallel to the central axis 31.

[0033] When pressure is applied to the working chamber 17 defined by the end face 20, the inner circumferential surface 23 and the actuator section 29 with the associated shaft seal 38, a pressure force is applied to the valve member 30, which leads to the actuating movement 48 from the rest position of the Fig. 1 into the functional position according to the Fig. 2. This also causes a displacement of the control pin 46 along the central axis 31, so that it can release the outlet opening 19 of the discharge channel 16 as soon as the valve member 30 assumes a corresponding position along the actuating path 48, whereby a release cross-section is provided for the outflow of control fluid from the working chamber 17 through the discharge channel 16, wherein the release cross-section corresponds, for example, to the cross-section of the outlet opening 19. Furthermore, during the actuating movement 48 of the valve member 30, an axial force is exerted on the return spring 40, which is supported with an end region opposite the end face 39 of the annular collar 36 on an axially aligned end face 49 of a support ring 50. The support ring 50 is designed purely as an example to be rotationally symmetrical to the central axis 31 and is accommodated in a fluid channel 51 designed as a stepped bore in the right base body section 11.

[0034] By way of example, it is provided that the support ring 50 has a coaxially aligned, annular support surface 52, which is supported on a corresponding annular surface 53 of the fluid channel 51. Furthermore, an annular groove 55 is formed on an outer peripheral surface 54 of the support ring 50, in which an O-ring sealing ring 56 is received, which is provided for sealing the fluid channel 51 against the recess 21 in the base body section 10. In addition, for sealing the fluid channel 51 against the recess 21, a shaft sealing ring 58 is provided on the base body 34 in an annular groove 57, which ensures a seal between the base body 34 and an inner peripheral surface 60 of the support ring 50 and ensures linear mobility of the valve member 30 relative to the support ring 50.

[0035] Furthermore, a rotationally symmetrical insert ring 61 is arranged in the fluid channel 51, purely by way of example, which is integrally connected to the support ring 50, which is penetrated by the valve member 30 and which is sealingly received on an inner circumferential surface 63 of the fluid channel 51 by means of a O-ring sealing ring 62. On an end face 64 of the insert ring 61 facing away from the actuator section 29, an annular circumferential cutting edge 65 is formed, which is also referred to as a valve seat. The cutting edge 65 is provided for the sealing engagement of a disk-shaped sealing element 67 received on the valve member 30 in a circumferential groove 66 of the sealing section 32. For example, the insert ring 61 is made of a dimensionally stable material, for example a metallic material or a plastic material, while the sealing element 67 is made of an elastic material, in particular a rubber-elastic material.

[0036] When the valve member 30 is displaced along the travel path 48 from the rest position according to the Fig. 1 into the functional position according to the Fig. 2, a fluidically communicating connection between the supply connection 5 and the working connections 6, 7, and 8 is released because the sealing element 67 is lifted from the cutting edge 65, in which it seals in the rest position. To ensure the most unhindered flow of working fluid from the supply connection 5 to the working connections 6, 7, and 8, the base body 34 of the valve member 30 is tapered adjacent to the sealing section 32, so that an annular cross-section is released between the base body 34 and the insert ring 61, through which the working fluid can flow.

[0037] A functioning of the valve arrangement 1 according to the Fig. 1 and Fig. 2 can be described as follows: initially, the control valve 2 is in the rest position according to the Fig. 1. The pilot valve 3 is also in the switching position as shown in the Fig. 1, so that a supply of control fluid into the fluid line 4 and from there into the working chamber 17 takes place. At this time, there is a fluid pressure in the working chamber 17 which is exclusively dependent on a fluid pressure in the discharge channel 16, since even in the rest position there is a fluidically communicating connection between the working chamber 17 and the discharge channel 16 via the annular gap 47. Furthermore, the valve member 30 is held in the rest position by the pre-tensioned return spring 40, wherein in the rest position a sealing contact is ensured between the sealing element 67 and the cutting edge 65 of the insert ring 61, referred to as the valve seat. Thus, in the rest position, purely by way of example, there is no fluidically communicating connection between the supply connection 5 and the working connections 6, 7 and 8.

[0038] When the pilot valve 3 is switched from the blocking position according to the Fig. 1 into the open position according to the Fig. 2, a supply of control fluid takes place from a fluid source 68 through the pilot valve 3 and along the fluid line 4 into the supply channel 15. The control fluid flows from the outlet opening 18 of the supply channel 15 into the working chamber 17. Since at this time the control pin 46 is immersed in the outlet opening 19 and thus adjustment of the control fluid valve can only take place through the annular gap 47 into the discharge channel 16, a fluid pressure for the control fluid quickly builds up in the working chamber 17, which at least almost corresponds to the fluid pressure of the fluid source 68.

[0039] This creates a pressure force acting on the valve member 30 along the central axis 31, which leads to an adjusting movement of the valve member 30 along the adjusting path 48 in the direction of the Fig. 2, provided the pressure force is greater than the restoring force of the return spring 40. In an initial phase (not shown in detail) of the relative movement of the valve member 30 along the travel path 48, the control pin 46 remains at least partially in the orifice 19, so that the annular gap 47 and the associated throttling effect for the discharge of the control fluid pressure through the discharge channel 16 are maintained, even though the working chamber 17 is enlarged by the movement of the valve member 30. This remains the case until, due to the relative movement of the valve member 30, the overlap of the control pin 46 with the orifice 19 is canceled and the full cross-section of the orifice 19 is thereby released.At this point in time, an acceleration of the valve member 30 along the actuating path 48 has already begun, the resulting actuating movement of the valve member 30 being maintained, with a suitable selection of the flow resistances in the supply channel 15 and in the discharge channel 16, even when the overlap between the control pin 46 and the orifice 19 is eliminated.

[0040] By way of example, it is provided that a flow resistance for an inflow of the control fluid into the working chamber is selected to be lower than a flow resistance for the outflow of the control fluid from the working chamber through the discharge channel 16, so that even when the orifice 19 is released, a fluid pressure is maintained in the working chamber 17 which is sufficient to effect the further actuating movement of the valve member 30 along the actuating path 48 until the valve member 30 has reached the Fig. 2 shows the opening position.

[0041] In the open position, the front surface 37 of the ring collar 36 comes into axial contact with a circular seating surface 69 of the valve bush 24. In the open position, as shown in Fig. Figure 2, due to the taper of the base body 34 of the valve element 30 provided adjacent to the ring groove 57, a large flow cross-section is released between the supply connection 5 and the working connections 6, 7 and 8, so that the working fluid provided at the supply connection 5 fills the fluid channel 51 and can escape through at least one of the working connections 6, 7 or 8.

[0042] When the pilot valve 3 is deactivated and the supply of control fluid to the supply channel 15 is interrupted accordingly, first, due to the drainage of the control fluid into the fully open mouth opening 19 of the supply channel 15, a rapid pressure drop occurs in the working space 17, so that the pressure force on the valve element 30, which was opposed to the restoring force of the return spring 40, almost instantaneously disappears. As a result, the return spring 40 can move the valve element 30 from the functional position according to the Fig. 2 towards the rest position according to the Fig. 1. This results in a reduction in the size of the working chamber 17, which is accompanied by a further outflow of control fluid from the working chamber 17 through the orifice 19 into the supply channel. The actuating movement of the valve member 30 towards the rest position is decelerated as soon as the control pin 16 dips into the orifice 19 of the supply channel 15 and the cross section of the orifice 19, which was free up to this point and is also referred to as the release cross section, is blocked by the control pin 46 at least almost completely except for the annular gap 47, which is also referred to as the throttle cross section.

[0043] Due to this narrowing of the available flow cross-section for the discharge of control fluid from the working chamber 17, a deceleration movement for the valve member 30 takes place, so that it is covered at a reduced speed along a section of the travel between the functional position and the rest position, which corresponds to a length extension of the control pin 46 over the end face 42 of the actuator section 29 along the central axis 31.

[0044] Purely by way of example, it is provided that the discharge channel 16 is coupled to an exhaust air line (not shown in detail), which is designed for the central discharge of control fluid from several valve assemblies 1 (not shown in detail). Alternatively, it can be provided that the discharge channel 16 opens into an environment without further measures or is provided with a silencer (also not shown) for damping the flow noise of the control fluid.

[0045] In the Fig. 3 and Fig. 4, the second embodiment of a valve arrangement 81 is different from the first embodiment of the valve arrangement 1 in that the valve member 110, which is otherwise identically constructed and provided with identical reference numerals for functionally identical components, has a connecting bore 82 extending from the bore 45, which enables a fluidically communicating connection between the supply connection 5 and the working chamber 17. The bore 45 serves as a discharge channel 96, wherein an opening 99 of the discharge channel 96 is formed on the end face 42 of the actuator section 109. In the rest position, according to the Fig.3, a control pin 126 is inserted, which is formed on an end face 100 of the recess 101 in the base body section 90 opposite the valve member 110. The mode of operation of the valve arrangement 81 is almost identical to the mode of operation of the valve arrangement 1 and differs essentially in that the control fluid can flow through the discharge channel 96 into the fluid channel 51 and can thus be used to supply fluid to an actuator (not shown).

Claims

[1] Valve arrangement (1; 81) with a control valve (2) which is designed to influence a working fluid flow and which comprises a base body (9; 89) on which an inlet connection (5) and an outlet connection (6, 7, 8) are formed, wherein the base body (9; 89) is penetrated by a fluid channel (51) which extends between the inlet connection (5) and the outlet connection (6, 7, 8), wherein a valve seat (65) is arranged in the fluid channel (51), which is designed for a sealing engagement of a valve member (30; 110) for blocking the fluid channel (51), wherein a valve member (30; 110) is arranged in the fluid channel (51), which valve member comprises an actuator section (29; 109) and a sealing section (32), wherein the actuator section (29; 109) is arranged along a travel path (48) between a closed position and an open position sealingly in an actuator recess (22) of the base body (9;89) and, together with the actuator recess (22), defines a variable-size working chamber (17), to which a supply channel (15) for supplying a control fluid flow into the actuator recess (22) and a discharge channel (16; 96) for discharging the control fluid flow from the actuator recess (22) are assigned, wherein the sealing section (32) is designed in the closed position for a sealing engagement with the valve seat (65) and in the open position for releasing the fluid channel (51), wherein the actuator section (29; 109) or the actuator recess (22) forms, with the discharge channel (16; 96), a discharge valve which is designed to influence the discharge of the control fluid flow into the discharge channel (16; 96) depending on a position of the valve member (30; 110) along the actuating path (48) is trained, ; characterized bythat a control projection (46; 126) is formed on an axially aligned end face (42) of the actuator section (29; 109) or on an axially aligned end face (20; 100) of the actuator recess (22), wherein a profile of an opening (19; 109) of the discharge channel (16; 96), which opens into the actuator recess (22), completely covers a profile of the control projection (46; 126). [2] Valve arrangement (1; 81) according to claim 1, characterized by that the discharge valve is designed to influence an inlet cross-section for the discharge channel (16; 96) between a release cross-section and a throttle cross-section, wherein the throttle cross-section is at least 5 percent and at most 25 percent of the release cross-section. [3] Valve arrangement (1; 81) according to claim 1, characterized bythat the control projection (46) is formed on the axially aligned end face (42) of the actuator section (29) and that the discharge channel (16) passes through the base body (9) and connects the mouth opening (19) of the discharge channel (16) to a discharge connection. [4] Valve arrangement (1; 81) according to claim 1, characterized by that the control projection (126) is formed on the axially aligned end face (100) of the actuator recess (22) and that the discharge channel (96) passes through the valve member (110) and connects the mouth opening (99) of the discharge channel (96) to the fluid channel (51). [5] Valve arrangement (1; 81) according to claim 3 or 4, characterized bythat the discharge channel (16; 96) is tapered at least in sections starting from the mouth opening (19; 99) along the actuating path (48) and / or that the control projection (46; 126) is tapered at least in sections starting from the end face (42) of the actuator section (29) or from the end face (100) of the actuator recess (22) along the actuating path (48). [6] Valve arrangement (1; 81) according to one of the preceding claims, characterized by that the actuator section (29; 109) is designed such that the supply channel (15) and the actuator recess (22) and the discharge channel (16; 96) are always fluidically connected to one another, regardless of the position of the valve member (30; 110) along the actuating path (48). [7] Valve arrangement (1; 81) according to one of the preceding claims, characterized bythat the supply channel (15) is assigned a pilot valve (3) which is designed to provide a control fluid flow to the supply channel (15) and which is designed as a solenoid valve or piezo valve. [8] Valve arrangement (1; 81) according to claim 7, characterized by that the pilot valve (3) is designed as a 2 / 2-way switching valve or as a 2 / 2-way proportional valve. [9] Valve arrangement (1; 81) according to claim 5, characterized by that the discharge channel (16; 96) is designed in the shape of a cone section starting from the mouth opening (19; 99) along the actuating path (48) and / or that the control projection (46; 126) is designed in the shape of a cone section starting from the end face (42) of the actuator section (29) or from the end face (100) of the actuator recess (22) along the actuating path (48).

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