Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
  • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
  • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
  • F15B13/0416—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor with means or adapted for load sensing
  • F15B13/0417—Load sensing elements; Internal fluid connections therefor; Anti-saturation or pressure-compensation valves
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/7722—Line condition change responsive valves
  • Y10T137/7837—Direct response valves [i.e., check valve type]

Definitions

• the invention relates to a hydraulic valve device having a fluid connection arrangement comprising at least one pressure supply port P for providing a pump pressure, a return port R, a section load sensing port LS two control ports P ⁇ and P'B and two Nutzan getting A, B to provide a Nutzanschluß horres and with a movable Control device for at least partially controlling individual terminals of the terminal arrangement, wherein the control device is preceded by a pressure compensator, and wherein the pressure compensator has a check valve.
• a hydraulic valve assembly is known with a supply connection arrangement having a high pressure port P and a low pressure port T, a working port arrangement having two working or Nutzan getting A, B, which are connectable to a consumer, a directional valve and a see between the directional valve and the supply port assembly P, T arranged compensation valve whose pressure output is connected to a pressure input of the directional valve, the compensation valve having a discharge output, which is connected to the pressure output is connectable and a movable from a starting position in opposite directions valve element in the form of a slide which is acted upon on one side by the pressure in the load-sensing line and the force of a spring and on the opposite side of the pressure at the pressure output, wherein the valve element when moving in a Direction a pressure control function and when moving in the opposite direction, a pressure relief function, wherein the slide has a longitudinal channel which is connected via a transverse bore to the pressure output and terminates in a first pressure chamber, and wherein the longitudinal
• the movable control device is preceded by a pressure compensator with an independent leakage discharge, wherein the pertinent relief output is connected to a load-sensing line, which communicates with the directional valve.
• a directional valve for controlling a consumer with two coaxially arranged spools is known, via the two connected to the consumer working ports A, B with a pressure supply port P or a return port R are connected and are biased in a normal position , in which between the spools a spring device is arranged with a spring element.
• the control slides can only be removed from each other to a certain extent by the "binding" of the centrally arranged spring element, so that the control slides in the In the basic position, essentially the bias of their respective external spring force is applied and occupies a defined basic position, which correspondingly increases the functional reliability of the known solution, and in this solution too, the control device is preceded by a pressure compensator in the hydraulic fluid direction.
• LUDV valve assembly is known in which a directional control valve forms a Zulaufmeßblende, which is followed by an individual pressure compensator.
• a hydraulic consumer is controlled, which is connected to two consumer or Nutzan say the control arrangement.
• Nutzan the control arrangement.
• two pressure chambers of the consumer can be connected to each other and to a pressure medium source.
• this connection of the two consumer connections takes place via a pressure medium flow path in which a check valve is arranged and / or the first-mentioned consumer connection is possible at high speed only via the pressure medium flow path and the opened non-return valve, thus preventing inadvertent movement of a hydraulic consumer in a rapid traverse position of the valve arrangement.
• a hydraulic valve device in particular for mobile working equipment, with a Block with a directional control valve with a metering orifice, with a together with the orifice a pressure medium flow regulating pressure compensator with a control piston which is displaceable in a bore of the housing block and a pressure surface acted upon by the load pressure has up, and with a load signal valve whose valve body in one opposite the control piston of the pressure compensator separate load signal valve housing is located and can also be acted upon by the load pressure.
• the load signal valve housing is inserted into the bore of the housing block and limited by the control piston of the pressure balance acted upon by the load pressure pressure chamber, the load signal valve used can be produced with little effort and its exchange is possible in a simple manner, so that a for so-called mono blocks well suited construction is realized.
• the thus constructed control device is preceded by a conventional pressure compensator, wherein the pressure compensator has a check valve which allows a check function when the pressure compensator is opened so that the respective Nutzanschlußtik can not drop below a briefly too low pump pressure, so as to ensure that when starting a hydraulic Consumer group against "standing loads” due to connected to the user terminals hydraulic consumers, a dangerous lowering of the load is avoided with certainty, especially if briefly the pump pressure for the control should prove too low while the check valve is permanently held in its closed position.
• the present invention seeks to provide a hydraulic valve device solution having an upstream pressure compensator, which builds compact together with the overall valve construction, which otherwise fluctuates little in operation. susceptible and thus functionally reliable and increases the control options with the valve device.
• This object is achieved by a valve device with the features of claim 1 in its entirety.
• Pressure compensator proves to be very stable in operation and is therefore not susceptible to vibration, which allows a defined continuous control of the consumer in the hydraulic circuit in both directions. Moreover, the pressure compensator builds compact, which overall benefits a compact space-saving overall valve design.
• valve device according to the invention Since by means of the check function certain fluid connection lines are controlled with, they need not be provided separately within the valve design, which helps further save space. Due to the desired modular system with modular individual components, the valve device according to the invention is also inexpensive to manufacture and otherwise reliable in use.
• the upstream pressure compensator within the valve device is preferably part of a proportional load sensing directional control valve with pump and return ports on the way valve axis.
• Circuit logic of the slide axis conditionally there are always at least one pressure supply port P and two return ports R present or alternatively two pressure supply ports P, PST and a return port R.
• valve device according to the invention will be explained in more detail with reference to an embodiment of the drawing. This show in principle and not to scale representation of the
• Figure 1 in the manner of a longitudinal section of an embodiment of the hydraulic valve device, wherein the simpler representation because of the non-return function for the pressure compensator in Figure 1 is not shown;
• FIG. 2 shows an enlarged illustration relative to FIG. 1 exclusively relative to the pressure compensator with a drawn-back function using a non-return valve.
• FIG. 1 shows a fluid connection arrangement designated as a whole by 10.
• the pertinent fluid connection arrangement 10 has a pressure supply connection P on, a return connection R, a section load-sensing connection LS, two control connections P'A and P'B and two utility connections A, B.
• the said fluid connections LS, P ' A , R, P and P'B, A and B are housed in a control housing 12, as seen in the viewing direction on the Fig.1, the lower end of the control housing 12 is provided with a pressure compensator 14 which the terminals LS, P ' A , R, P and P'B is connected upstream and controls this extent. With the thus upstream pressure compensator 14 is the so-called.
• a control device 18 of the valve device as such is actuated in a known and therefore not described in more detail manner of conventional pilot valves, which are shown for ease of illustration in Figure 1 only insofar as their respective assignable pilot housing 24,26 are addressed.
• the two pilot valves for the control device 18 supply two counteracting control pressures XA and XB.
• a pump control pressure PST then acts on the respective pilot valve, which in each case forms a further P connection within the variant presented here.
• a tank connection line T 0 is also connected to the respective pilot valve.
• Said control device 18 has a horizontally displaceable in the direction of view of Figure 1 control slide 28, which is shown in Figure 1 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.
• the pertinent structure is customary in 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 spool 28 is provided with load-sensing terminals 32,34 and load-sensing terminals 36,38, which are interconnected in pairs carrying fluid.
• the first load-sensing terminal 32 is fluidly connected to the second load-sensing terminal 38, and the second load-indicating terminal 34 is in fluid communication with the first load-sensing terminal 36.
• Said reporting terminals and sense terminals are formed in the spool 28 in the form of radial cross-bores and, as the case may be, which axial displacement position of the control slide 28 assumes, 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.
• connecting channels 40, 42 arranged within the control slide 28 are used.
• one of the connecting channels 40 is designed as a so-called center channel which, in the neutral position of the control device 18 shown in FIG. 1, covers the region between the section load-sensing connection LS and the useful connection B with its axial length.
• the center channel is seen in the direction of the Fig.1 on the left side of the spool 28 and extends in the manner of an attached blind bore along the longitudinal axis of the spool 28.
• a further connecting channel 42 at least one annular longitudinal channel which in turn covers in the neutral position of the control device 18 with its axial length at least the region between the control connection P ⁇ and the useful connection A.
• the load-indicating and load-sensing connections 32, 36, 34, 38 are each designed as radially extending bores in the control slide 28.
• the middle channel 40 is limited to generate the channel guide in this respect by an insert sleeve 44 which at least partially along its whyfan- ges arranged in a predetermined central region with the inner wall of the spool 28 in this area limits the annular longitudinal channel 42, which may also be formed from a plurality of concentric with the central channel 40 individual channels (not shown).
• the axial length of the insert sleeve 44 extends according to the illustration of Figure 1 between the first load reporting terminal 32 and a narrowed offset between the first Lastgelanschluß 36 and second Lastgranlanschluß 38 in the height of the return port R.
• 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.
• the hydraulic valve device shown forms a so-called. LS directional control valve with upstream pressure compensator 14.
• This valve devices are used basically to hedge parts of the hydraulic circuit, for which additionally a not-shown pressure relief valve may be provided and the load-sensing portion LS is compared to LS ma ⁇ preferably by means of a shuttle valve (not shown).
• the hydraulic valve device has the construction length of a short valve axis design with respect to known solutions fewer ring channels.
• FIG. 2 also showing the non-return function of the pressure compensator 14, which was omitted in FIG. 1 for the sake of simpler presentation .
• the Fig.2 corresponds to the lower half of Figure 1, seen in the direction of Fig.1 below the control device 18, the pressure compensator 14, which is so far taken in the same control housing 12 of the overall valve device.
• the pressure compensator 14 has a check valve 56 whose non-return function is used with open pressure compensator and ensures that the respective Nutzanschluß réelle at the Nutzanschluß A or B can not drop below a briefly too low pump pressure, which will be explained in more detail below ,
• the check valve 56 acts with its non-return function on the control terminal P'e; but there are also other configurations conceivable, for example, in which the check valve 56 then acts on the control terminal P'A or on both sides of both control terminals P ⁇ and P'B in reverse functional arrangement.
• the check valve 56 has a valve body 58, which is supported on a valve spring designed as a compression spring 60. Seen in the direction of FIG.
• valve spring 60 attempts to push the valve body 58 to the left, in order to hold it in such a manner in abutment with parts of a control piston 62 of the pressure compensator 14.
• the pertinent control piston 62 is supported at its other end against a likewise If the valve body 58 of the check valve 56 is in contact with the control piston 62 as shown in FIG opposite direction both the control spring 64 and the valve spring 60 a.
• the control piston 62 has passage openings divided into individual functional groups, with the first group 66 being assigned to the control connection P ⁇ and the second group 68 being assigned to the control connection P ' B.
• the third group 70 is assigned to the pressure supply connection P and the fourth group 72 is formed in the manner of relief holes, the return port R is assigned. Except for the fourth group 72, the other groups 66,68,70 are formed of two adjacent rows of passages with different bore diameters, which helps to facilitate the control function for the pressure compensator 14.
• control spring 62 is also supported with its other free end, which faces away from the check valve 56, on wall parts 74 of the pressure balance housing, which to this extent is part of the control housing 12. Moreover, the control spring 64 is received in the spring chamber 16 of the control housing 12 and the spring chamber 16 is so far in media connection with the section load-LS, which can be equipped with a pressure limiting function, not shown, for example, using a pressure relief valve, not shown.
• valve body 58 in a control function of the control piston 62, the valve body 58 with its left free end at least partially releases the second group 68 at passage openings in the direction of the control port P'B.
• the pertinent second group 68 and thus the said fluid away blocked by the valve body 58 which is supported so far with its free end face on a shoulder 78 of the control piston 62.
• the valve body 58 at its facing in the direction of the interior of the control piston 62 end face a recess 80, preferably in the form of an inwardly facing cone on.
• the maximum stroke shown in Figure 2 of the valve body 58 of the check valve 56 is so far limited in its closing direction by a limiting device 82 having a stop screw, which, as shown, engages with its free end 84 in a recess of the valve body 58 and the screw head 86th abuts a boundary wall 87 of a screw-in 90, which is screwed in a sealing manner in the pressure compensator housing and in the repair and assembly case after its removal allows access to the inner parts of the pressure compensator 14.
• the control spring 64 pushes the control piston 62 in the direction of FIG. 2 seen to the right and the right free end 92 of the control piston 62 strikes against the adjacent end 94 of Then screw-in part 90.
• the pressure compensator 14 has a first pressure outlet to P ⁇ and a second pressure outlet to P'B to supply the spool 28, the controller 18.
• the two pressure outputs to P ⁇ and P'B without additional additional lines by the pressure compensator 14 itself pressure-equalizing connect, which helps save space.
• the supply connection P of the pressure compensator 14 is seen in the longitudinal direction so seen between the two pressure outputs to P ⁇ and P'B formed by the already mentioned control connections.
• the Pressure compensator 14 via the additional return port R, which is located between the pressure supply port P and the control spring 64.
• the pressure in the pressure compensator 14 increases and the resulting Compression force pushes the control piston 62 against the control spring 64 until the P - control edge 96 just closes. If pressure fluid under high pressure continues to enter the pressure compensator 14 due to gap leakage, then the control piston 62 continues to move against the control spring 64 until the R control edge opens and the undesired overpressure degrades to such an extent until the working pressure in the control connections P ⁇ and P'B just keeps the control pressure of the control spring 64 in balance.
• ground contact force the mowing head is pulled over the ground contour. Will he be informed of an pulled exercise, then the mowing head raises alike, with hydraulic fluid is removed from the control terminal P'B. Consequently, the pressure at the control port P'B decreases and the control piston 62 moves into an opening position and allows pressure fluid to flow in from the pressure supply port P until force balance on the pressure compensator 14 is reached again.
• the cutting head sinks and presses hydraulic fluid into the control connection P ' B. There, the pressure rises and the control piston 62 moves against the control spring 64. In this case, the return port R is opened and the hydraulic fluid flows off until again force balance on the control piston 62 has occurred. However, the valve body 58 of the check valve 56 can only prevent the reflux until the control piston 62 has closed approximately the P control edge 96. If the control piston 62 continues to move against the control spring 64, then the valve body 58 is held in its position by the limiting device 82 described, thus remaining in that respect, and a return flow cross-section opens.
• the check valve 56 in the pressure compensator 14 thus prevents the load from falling back into the pressure supply connection P. If, for example, the mowing head continues to be raised from a stopped position with a weight load corresponding to 150 bar, the following functional situation takes place. From a neutral position of the pressure system, the spool 28 is deflected and the load of 150 bar is reported on the one hand to the pressure compensator 14 and on the other hand to a not shown in detail D ruck tively I system (pump regulator or circulation pressure compensator). Building up the pump pressure can take a few tenths of a second.
• control piston 62 has already run to its stop under the influence of the reported 150 bar on the spring side and has thus opened the supply port P to the maximum. net.
• the load pressure of 150 bar to the pressure output P ' B of the pressure compensator 14 has prevailed.
• the control piston 62 remains but in the fully open position, because on both of its front sides, the same pressure acts and the spring force generates the excess of force to hold the open position.
• the check valve 56 is closed, namely until the pump pressure has increased to over 150 bar and the lifting - ride can begin.
• the pressure compensator described has a connection to the tank return, which may be formed by the return port R.
• a sufficient cross-section to the tank can be opened with the result that medium flowing back into the tank can be passed (pressure regulation) and not only in the outflow direction to the working area.
• the integrated non-return valve saves installation space and in its optional version with maximum closing stroke (screw head), it guarantees a pressure regulation that allows a return flow from the respective working connection to the pressure compensator and the tank connection.
• the pressure compensator moves into the tank connection and the check valve seat is no longer accessible in this control position. Particular importance is attached to the fact that the return port R occupies a central central position within the indicated connection points of Figure 1.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Fluid-Pressure Circuits (AREA)
• Servomotors (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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Citations (3)

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• 2007
  • 2007-11-14 DE DE200710054135 patent/DE102007054135A1/de not_active Withdrawn
• 2008
  • 2008-11-13 EP EP20080849706 patent/EP2220379B8/de not_active Not-in-force
  • 2008-11-13 JP JP2010533493A patent/JP2011503483A/ja not_active Ceased
  • 2008-11-13 US US12/734,286 patent/US20110132476A1/en not_active Abandoned
  • 2008-11-13 DK DK08849706T patent/DK2220379T3/da active
  • 2008-11-13 WO PCT/EP2008/009578 patent/WO2009062707A1/de not_active Ceased

Patent Citations (3)

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