EP2220380B1 - Hydraulic valve device - Google Patents

Description

• einen Druckversorgungsanschluß P
• einen Rücklaufanschluß R
• einen Sektionsloadsensing-Anschluß LS
• zwei Steueranschlüsse P_A' und P_B' sowie
• zwei Nutzanschlüsse A,B

und mit einer verfahrbaren Steuereinrichtung zum zumindest teilweisen Ansteuern von Anschlüssen der Fluidanschlußanordnung gemäß der Merkmalsausgestaltung des Oberbegriffes des Patentanspruches 1.The invention relates to a hydraulic valve device with a fluid connection arrangement, comprising at least

• a pressure supply port P
• a return port R
• a section load-sensing port LS
• two control terminals P _A 'and P _B ' and
• two service ports A, B

and with a movable control device for at least partially controlling connections of the fluid connection arrangement according to the feature configuration of the preamble of claim 1.

By the DE 603 04 663 T2 a hydraulic valve assembly is known with a supply port assembly having a high pressure port P and a low pressure port T, a working port arrangement comprising two working or Nutzanschlüsse A, B, which are connectable to a consumer, a directional valve and between the directional valve and the supply port arrangement P, T arranged compensation valve whose pressure output is connected to a pressure input of the directional valve, wherein the compensation valve has a discharge outlet, which is connectable to the pressure outlet and a movable from an initial position in opposite directions valve element in the form of a slide on one side of the pressure in the load-sensing line and the force of a spring and acted on the opposite side of the pressure at the pressure outlet is, wherein the valve element when moving in one direction, a pressure regulating function and when moving in the opposite direction performs a pressure relief function, wherein the slide has a longitudinal channel, which is connected via a transverse bore to the pressure output and ends in a first pressure chamber, and wherein the longitudinal channel beyond the transverse bore and can be connected via a closable opening with a second pressure chamber, in which there is a relief pressure.

With this known solution, it is possible to counteract so-called parasitic pressure propagation, as may occur especially at higher pressures. If, then, with concomitant virtually unavoidable leakage, the pressure propagates up to an actuation motor which should not be actuated, and then sets it in motion, unwanted and dangerous ways of lifting loads may occur. In this context, previously used safety valves, however, may also be leaking and even contribute to the emergence of parasitic pressure propagation even with.

By the EP 1 370 773 B1 a similar directional valve is known as a hydraulic valve device, which is used to control the pressure and flow of hydraulic oil to or from working ports A, B at least one consumer, wherein the pressure and the flow by means of at least one actuator operable in a slide bore displaceable spool as a movable control device and thus operatively connected annular channels is controllable, wherein in the center of symmetry on a symmetry axis of the valve device a tank connection annular channel is arranged as so-called. Return connection and on both sides further existing ring channels are also arranged symmetrically to the axis of symmetry. Due to the aforementioned symmetrical structure this is in the known solution so far from a constructive point of view simple and allows a cost-effective production. Also, the known valve device should have an improved dynamic switching behavior and have a large range of functions.

• einen Druckversorgungsanschluß P,
• einen Rücklaufanschluß R,
• einen Sektions-Loadsensinganschluß LS,
• zwei Steueranschlüsse P_A' und P_B' sowie
• zwei Nutzanschlüsse A,B

und mit einer verfahrbaren Steuereinrichtung zum zumindest teilweisen Ansteuern von Anschlüssen der Fluidanschlußanordnung, wobei die Steuereinrichtung mit Lastmelde- und Lastfühlanschlüssen versehen ist, die paarweise miteinander verschaltet einen Lastmeldeanschluß einem Fühlanschluß zuordnen und die in Abhängigkeit der Verfahrstellung der Steuereinrichtung zumindest einen Teil der Anschlüsse der Fluidanschlußanordnung fluidführend miteinander verbinden, wobei die Steuereinrichtung einen Steuerschieber aufweist mit fluidführenden Verbindungskanälen, die die paarweise einander zuordenbaren Lastmelde- und Lastfühlanschlüsse miteinander verbinden, und wobei mindestens einer der Verbindungskanäle als Mittenkanal und mindestens ein weiterer der Verbindungskanäle als Ringlängskanal ausgebildet ist, der in der Neutralstellung der Steuereinrichtung mit seiner axialen Länge zumindest den Bereich zwischen Steueranschluß und Nutzanschluß abdeckt.By the DE 88 01 058 U1 a generic hydraulic valve device is known, including at least

• a pressure supply port P,
• a return port R,
• a section load-sensing terminal LS,
• two control terminals P _A 'and P _B ' and
• two service ports A, B

and with a movable control device for at least partially controlling connections of the fluid connection arrangement, wherein the control device is provided with Lastmelde- and Lastfühlanschlüssen, interconnected in pairs interconnect a load detection connection to a sensing connection and the fluid depending on the Verfahrstellung the control device at least a portion of the terminals of the fluid connection arrangement connect to each other, wherein the control device comprises a spool with fluid-carrying connection channels, which connect the pair-assignable Lastmelde- and load-sensing connections, and wherein at least one of the connecting channels as a central channel and at least one of the connecting channels is formed as a ring longitudinal channel, in the neutral position of the control device covers with its axial length at least the area between the control terminal and the user terminal.

Comparable solutions with arranged in a valve spool Lastmelde- and load sensing connections are also by the US-A-4,253,482 . US-A-3 565 110 and EP-A-0 786 598 known.

The known solutions, however, are still rather expensive to manufacture and are basically to be adapted and designed accordingly for each fluidic application. Also, the known solutions in the prior art, as far as the functional safety, still leaves something to be desired.

Based on this state of the art, the invention is based on the object to further improve this while maintaining its advantages that the reliability is further increased and that the solution according to the invention can be well designed with respect to changing applications in terms of a modular system , This object is achieved by a hydraulic valve device having the features in the entirety of claim 1.

Characterized in that according to the characterizing part of claim 1, the center channel is bounded by an insert sleeve which limits along its outer circumference with the inner wall of the control device the respective annular longitudinal channel, the control device can be easily adapted to a variety of fluidic applications use cases in the sense of a modular building block concept that thereby larger conversion or adaptation work on the hydraulic valve device are necessary. Due to the asymmetric structure of the control device, which acts so far on the fluid connection arrangement, a safe control behavior is achieved and the controller can be so far with a very favorable dynamic travel behavior position accurately in the functional positions bring. The solution according to the invention also constructs a short construction, so that all relevant switching and control positions for the hydraulic valve devices can be realized in a small installation space. In a particularly preferred embodiment of the hydraulic valve device according to the invention, it is provided that the control device can also assume a so-called floating position, without there being any loss of resolution in the lowering and lifting region relative to the working or utility connections A, B. Although, as shown, the proportional range in lifting and lowering is fully maintained, the housing length is still kept short in length due to the special design of the control device, to which the asymmetric design of the hydraulic valve device contributes.

In a further, particularly preferred embodiment of the solution according to the invention, the control device is preceded by a pressure compensator with which the so-called quantity cut-off is possible by means of a load-sensing pressure limitation in the spring chamber of the pressure compensator. In the known in the prior art solutions with downstream pressure compensator this function of Mengenabschneidung is not possible or to obtain only over appropriate additional valve constructions in a complex manner. In particular, the control function of the pressure compensator is improved by a relatively large outflow cross-section opens into the return port. Also, the so-called. Floating position is improved.

Fig.1 und 2

in der Art eines Längsschnittes zwei Ausführungsbeispiele der hydraulischen Ventilvorrichtung, wobei sich die Druckwaage in ihrer jeweil igen Regelstellung befindet;

Fig.3

in der Art eines Schaltplanes die Lösung der Ventilvorrichtung nach den Fig.1 und 2;

Fig.4

in Längsschnittdarstellung eine perspektivische Ansicht auf den Steuerschieber betreffend "Schwimmstellung und Eilgang" in Stellung "Eilgang" und mit seinen verschiedenen Anschlußstellen; und

Fig.5

eine vereinfachte Längsschnittdarstellung durch eine Ausführungsform des Steuerschiebers, die nicht Teil der Erfindung ist, mit seinen diversen Anschlußstellen; in der oberen Bildhälfte in Neutralstellung gezeigt, in der unteren Bildhälfte in ausgelenkter Betätigungsstellung.

In the following the hydraulic valve device according to the invention will be explained in more detail with reference to various embodiments. This show in principle and not to scale representation of the

Fig.1 and 2

in the manner of a longitudinal section two embodiments of the hydraulic valve device, wherein the pressure compensator is in their respective control position;

Figure 3

in the manner of a circuit diagram, the solution of the valve device according to the Fig.1 and 2 ;

Figure 4

in longitudinal section a perspective view of the spool regarding "floating position and rapid traverse" in position "rapid traverse" and with its various connection points; and

Figure 5

a simplified longitudinal section through an embodiment of the spool, which is not part of the invention, with its various connection points; in the upper half of the picture shown in neutral position, in the lower half in deflected operating position.

The Fig.1 shows a designated as a whole with 10 fluid port arrangement. The pertinent fluid port assembly 10 has a pressure supply port P, a return port R, a section load sensing port LS, two control ports P _A 'and P _B ' and two payload ports A, B on. The aforementioned fluid ports LS, P _A ', R, P and P _B ', A and B are housed in a control housing 12, wherein in the direction of the Fig.1 seen the lower end of the control housing 12 is provided with a per se conventional pressure compensator 14, which is the terminals LS, P _A ', R, P and P _B ' upstream and this controls so far. With the pressure compensator 14 preceded by this, the function quantity cutoff is achieved by means of an LS pressure limitation in the spring chamber 16 of the pressure compensator, whereby a quantity cutoff makes sense, for example, if a steering cylinder connected to the useful connections A, B, is at the stop and you want to cut off the inflow to the extent to avoid overloads.

The control device 18 as such is controlled in a known and therefore not described in more detail manner of conventional pilot valves 20,22, which in the Figure 3 are reproduced with their hydraulic symbols and the sake of ease of representation in the Fig.1 are shown only insofar as their respective assignable pilot housing 24,26 are addressed. On the output side, the two pilot valves 20, 22 for the control device 18 supply two counteracting control pressures X _A and X _B, respectively. Furthermore, a pump control pressure P _ST acts on the respective pilot valve 20, 22 and a tank connection line T _O is likewise connected to the respective pilot valve.

The aforementioned control device 18 has a viewing direction on the Fig.1 seen horizontally displaceable spool 28, in the Fig.1 is shown in its undeflected middle or neutral position. The pertinent neutral position of the spool 28 is supported by two spring memory, which are designed as compression springs 30 and are integrated in a respective assignable spring chamber in the pilot housings 24,26. Also, the pertinent structure is known in the pertinent hydraulic valve devices, so that in this respect will not be discussed in more detail here at this point. The control device 18 with control slide 28 is provided with anti-swirl connections 32, 34 as well as with load-sensing connections 36, 38, which are interconnected in pairs to carry fluid. Namely, the first load-avoidance port 32 is fluidly connected to the second load-sensing port 38 and the second load-sensing port 34 is in fluid communication with the first load-sensing port 36. Said reporting ports and sensing ports are inserted into the spool 18 in the form of radial cross-bores and depending on which axial Verfahrstellung the spool 18 occupies the said connections 32, 34, 36 and 38 come into fluid-conducting or blocking connection with the respectively assignable connections of the fluid connection arrangement 10.

The type of possible switching positions results from the usual circuit diagram after Figure 3 , so that this will not be discussed in detail. For producing the fluid-carrying connection between the pair-wise assignable load-sensing and load-sensing connections 32, 36; 34,38 serve within the spool 18 arranged connection channels 40,42. In this case, one of the connecting channels 40 is designed as a so-called. Center channel, in the in the Fig.1 shown neutral position of the control device 18 with its axial length covers the area between the section load-sensing connection LS and the Nutzanschluß B. In that regard, the center channel is in the direction of the Fig.1 In paral leler arrangement this is provided as a further connecting channel 42 at least one annular longitudinal channel, which in turn in the neutral position of the control device 18 with its axial length covers at least the area between the control terminal P _A 'and user port A. The Lastmelde- and Lastfühlanschlüsse 32,36; 34,38 are each formed as radially extending Boh ments in the spool 28.

The middle channel 40 is limited to produce the channel guides insofar by an insert sleeve 44 which at least partially along its outer periphery in a predetermined center region arranged with the inner wall of the spool 28 in this area limits the longitudinal annular channel 42, which is so far from a plurality of concentric to the center channel 40 arranged individual channels (not shown) may be formed. The axial length of the insert sleeve 44 extends as shown in the Fig.1 between the first load-signaling connection 32 and a narrowed offset point between the first load-sensing connection 36 and the second load-sensing connection 38 in the height of the return connection R. While the insertion sleeve 44 with its one, in the direction of the Fig.1 seen right end is supported on said bottleneck within the longitudinal bore of the spool 28, the opposite other free end in the region of the first load signaling connection 32 is based on a compression spring, which extends in this respect between a closure plug 46 and the free end of the sleeve and insofar with a predeterminable Preload holding the insert sleeve 44 in position. About the pertinent arrangement can be optionally existing length tolerances in the system, insert sleeve 44 to spool 28, compensate.

How the other Fig.1 shows, the spool 28 along its outer periphery two longitudinal control channels 48,50, which open in the neutral position of the control device 18 respectively in the Nutzanschluß A and the Nutzanschluß B. In that regard, opens in the neutral position of the spool 28 shown, the load sensing bore 36 under the housing wall between the user port A and the return port R.

Overall, the hydraulic valve device forms a so-called. LS directional control valve with upstream pressure compensator 14. As the switch position after the Figure 3 shows, at least one pressure relief valve 52 is provided for securing parts of the hydraulic circuit, and the load-sensing LS is compared with LS max by means of a shuttle valve 54 abgegl ichen.

The hydraulic valve device according to the invention is designed as a LS-way valve with upstream pressure compensator 14 and has a valve-length of the construction short design on with respect to known solutions less ring channels. With the upstream pressure compensator 14 is the function already described quantity cut by LS-pressure limitation in the spring chamber of the pressure compensator 14 possible.

The embodiment described below after the Fig.2 relates to a so-called. Floating position solution, wherein the pertinent valve assembly comparable to the valve assembly according to Fig. 1 is. In that regard, also in the solution after the Fig.2 The same components are denoted by the same reference numerals and the comments made so far then apply to the modified embodiment. The latter will be described below only to the extent that they are structurally substantially different from the embodiment described above Fig.1 different.

In the embodiment of the Fig.2 the spool 28 along its outer periphery between the two groove-like control channels 48,50 still separate pockets 56 which are separated from each other in unterschiedfichen angular arrangements along said spool 28 extend. Further, in the control channel 48, at least in the region of the user port A, a segmenting partition wall 58 is retracted and in the in the Fig.2 shown floating position is the user port A in fluid-carrying connection with the individual pockets 56 of the spool 28th

With the valve arrangement shown in the Fig.2 using additional pockets 56 between the two control channels 48,50 can reach a floating position for the valve without loss of resolution in lowering and lifting area of the hydraulic arrangement.

With the valve device solution according to the invention, it is possible to solve the combination of a floating position and a rapid traverse in a mobile valve in slide construction, which is useful in particular for use in conventional machines (not shown), in which work equipment to move quickly and / or if these in a way Pivoting off or hang up, which is the case for example for a mower bar a slope mower od. Like.

The representation after the Figure 4 , which represents only the spool 28 together with the housing connections LS, P _A ', A, R, B, P _B ' contributes so far for the realization of a pertinent rapid traverse with. In the rapid traverse position, the fluid-carrying connection P is maintained after B, the compound A is closed to R and for the connection A to P is opened to the return flow from the rod side (ring surface) of a working cylinder of the machine not shown to the bottom side (bar mower application) to enable. The one load sensing bore of the spool 28 is in the pressure port B and a load detection hole is guided to a assignable housing pocket in the spool 28. The pertinent Lastmeldebohrung ends so far on the lateral surface of the spool 28, wherein the lateral surface is guided around the outlet of the detection hole locally. Otherwise, the lateral surface is here opened and recessed to create a return flow from A to P. Thus, the rotational position of the load detection bore and housing pocket is maintained, not shown, mechanical anti-rotation for the spool 28 is present. The further load-sensing bore is then in the R-channel and the corresponding further load-sensing bore is under the housing wall between P _A 'and the A-channel. A rapid traverse position of the spool 28 is achieved in each case by an overstroke on the so-called. Lifting position and the floating position on the so-called. Lowering position of the connected hydraulic components of the machine. This corresponds to the desired working conditions at the mentioned machines, because the rapid traverse as switching position should not be switched on directly from "neutral", in order to avoid an excessive switching pressure.

Since the message channel of the load-sensing pressure must be open in the spring chamber of the section pressure balance over the entire stroke of the spool 28, can be based on this function no shortening of the valve axis, which would have a favorable effect on the size of the valve device. In contrast, an improvement in the coverage of the message bore on the spool 28 can be achieved. In the proposal according to the invention after the Fig. 1 and 2 the LS signaling holes travel into the pressure channels as far as the float position is addressed there. In order to avoid a malfunction in the form of an unauthorized flow from other pressure channels in the LS reporting circuit, additional means are used in the form of check valves 60 as shown in FIG Figure 5 which is not part of the invention.

In the neutral position of the spool 28 (shown in the upper half), the radial load sensing bore and the radial load sensing bore are each covered by the housing wall. The concept of the short design requires that in the position "lifting" (working position of the working machine) drives the load detection hole of the terminal A in the P port and the load sensing bore in the R port. To avoid a short circuit from P to R, a check valve 60 is installed in the corresponding connecting line 62. In the so-called. Lower position and in the neutral position, a spring holds the check valve 60 then open, so that both a pressure message is guaranteed as well as a dynamic flow, which is due to the control movements of the connected pressure compensator 14.

The pressure drop at the check valve at rapid control movements of the pressure compensator 14 and the spring force are coordinated so that at fast control movements, as they correspond to a high flow, the check valve 60 can not close. In the lifting position, however, the leakage flow from P to R immediately becomes so high that the Pressure drop across the open check valve 60 overcomes the spring force and the check valve closes safely. In that regard, therefore, the floating position is achieved by overtravel on the lowering position and the lifting position of each connected machine. In that regard, it is possible that only when the implement has been placed in the lowered position, for example, on the ground, then the floating position is turned on.

The in the Figure 5 check valves 60 shown can also in the embodiment of the Fig.1 and 2 are used in the local control channels 48,50 (not shown), in which case the closing ball opens in each case in the direction of the load-sensing connection in order to achieve comparable results, as described above.

With the valve device according to the invention can be standard way valves with the three basic positions for neutral, lifting and lowering extend in scope to a floating position and / or a rapid traverse, without this, as in the known slide valve solutions, comes to an extension of the slide stroke to to get into the additional position with the desired logical operations; Rather, with the solution according to the invention, a pusher slide extension can be completely avoided or the slide valve axis can even be shortened.

Claims (15)

1. A hydraulic valve device with a fluid connector arrangement (10) containing at least

   - a pressure supply connector (P),

   - a return flow connector (R),

   - a section load sensing connector LS,

   - two control connectors (P_A') and (P_B'), and

   - two utility connectors (A, B)

   and with a displaceable control means (18) for at least partially triggering connectors of the fluid connector arrangement (10), the control means (18) being provided with load reporting and load sensing connectors (32, 34; 36, 38) which, interconnected in pairs, assign one load reporting connector to one sensing connector (32, 38; 34, 36) and which, depending on the position of movement of the control means (18), interconnect at least some of the connectors of the fluid connector arrangement (10) to carry fluid, the control means (18) having a control spool (28) with fluid-carrying connecting channels (40, 42) which interconnect the load reporting and load sensing connectors (32, 36; 34, 38) which can be assigned to one another in pairs, and at least one of the connecting channels (40) being made as a middle channel and at least one other of the connecting channels (42) being made as a longitudinal annular channel which, in the neutral position of the control means (18), with its axial length covers at least the region between the control connector (P_A') and the utility connector (A), characterised in that the middle channel (40) is bordered by an insertion sleeve (44) which limits the respective longitudinal annular channel (42) along its outside periphery with the inside wall of the control means (18).
2. The valve device according to Claim 1, characterised in that in the neutral position of the control means (18) the middle channel (40) covers the region between the section load sensing connector (LS) and the utility connector (B) with its axial length.
3. The valve device according to Claim 1 or 2, characterised in that the control means (18) can be triggered by two pilot valves (20, 22) which act in opposite directions, and is held spring-centred in its neutral position.
4. The valve device according to any of Claims 1 to 3, characterised in that the control spool (28) along its outer periphery has at least two groove-like control channels (48, 50) which are oriented lengthwise and which, in the neutral position of the control means (18), discharge into the utility connector (A) and the utility connector (B) respectively.
5. The valve device according to Claim 4, characterised in that in the neutral position of the control spool (28), one radial load sensing bore (36, 38) at a time offset on the periphery to the assignable control channel (48, 50) ends under that housing partition which is situated between the utility connectors (A, B) and the return flow connector (R).
6. The valve device according to Claim 5, characterised in that the load sensing bores (36, 38) are separated fluid-tight from one another.
7. The valve device according to any of Claims 1 to 6, characterised in that in the neutral position of the control spool (28), the radial load reporting bores (32, 34) each discharge on both sides next to the section load sensing connector (LS) and are covered by a housing wall.
8. The valve device according to any of Claims 4 to 7, characterised in that in the neutral position of the control spool (28) a longitudinal channel in the control spool (28) connects the section load sensing connector (LS) to a trigger space (X_A) of the device to carry fluid.
9. The valve device according to any of Claims 1 to 8, characterised in that a pressure compensator (14), which also at least partially triggers the fluid connector arrangement (10), is connected upstream to the control means (18) with its fluid connectors.
10. The valve device according to any of Claims 5 to 9, characterised in that in a floating position of the control spool (28), one of its annular channels (48), which discharges into the utility connector (A), contains a partition (58) that separates the control connector (P_A') from the utility connector (A).
11. The valve device according to any of Claims 1 to 10, characterised in that at least for some of the connecting channels (40, 42) between the load reporting and load sensing connectors, which can be assigned to one another in pairs, at least one check valve (60) is inserted.
12. The valve device according to Claim 11, characterised in that the respective check valve (60) within the connecting channels closes in the direction of load sensing A and load reporting B or load sensing B and load reporting A.
13. The valve device according to Claim 11, characterised in that the control spool (28) can be displaced beyond a maximum working position into a quick traverse position.
14. The valve device according to Claim 11, characterised in that the control spool (28) in its quick traverse position connects the control connector (P_B') to the utility connector (B) by means of a control groove (50) and by its additional pocket-like connecting channels between the reporting bores (LS_A) connects the utility connector (A) and the control connector (P_A).
15. The valve device according to Claim 11, characterised in that the load reporting bores (LS_A) and (LS_B) of the control spool (28) are aligned in their rotary position to the local widenings of the section load sensing connector (LS).

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