EP1934487B1 - Hydraulische steuervorrichtung - Google Patents

Hydraulische steuervorrichtung Download PDF

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Publication number
EP1934487B1
EP1934487B1 EP06828803A EP06828803A EP1934487B1 EP 1934487 B1 EP1934487 B1 EP 1934487B1 EP 06828803 A EP06828803 A EP 06828803A EP 06828803 A EP06828803 A EP 06828803A EP 1934487 B1 EP1934487 B1 EP 1934487B1
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EP
European Patent Office
Prior art keywords
pressure
control
valve
hydraulic
load
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Not-in-force
Application number
EP06828803A
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German (de)
English (en)
French (fr)
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EP1934487A1 (de
Inventor
Wolfgang Kauss
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Bosch Rexroth AG
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Bosch Rexroth AG
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Publication of EP1934487A1 publication Critical patent/EP1934487A1/de
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Publication of EP1934487B1 publication Critical patent/EP1934487B1/de
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    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/162—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for giving priority to particular servomotors or users
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/05—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed specially adapted to maintain constant speed, e.g. pressure-compensated, load-responsive
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/165—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for adjusting the pump output or bypass in response to demand
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20546—Type of pump variable capacity
    • F15B2211/20553—Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/25—Pressure control functions
    • F15B2211/253—Pressure margin control, e.g. pump pressure in relation to load pressure
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
    • F15B2211/3053—In combination with a pressure compensating valve
    • F15B2211/30535—In combination with a pressure compensating valve the pressure compensating valve is arranged between pressure source and directional control valve
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3105—Neutral or centre positions
    • F15B2211/3111—Neutral or centre positions the pump port being closed in the centre position, e.g. so-called closed centre
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3144—Directional control characterised by the positions of the valve element the positions being continuously variable, e.g. as realised by proportional valves
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/605—Load sensing circuits
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7053—Double-acting output members
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/78—Control of multiple output members
    • F15B2211/781—Control of multiple output members one or more output members having priority

Definitions

  • the invention relates to a hydraulic control device for a priority hydraulic consumer and a subordinate hydraulic consumer, according to the preamble of patent claim 1.
  • Such a hydraulic control circuit is from the DE 197 03 997 A1 known.
  • the two hydraulic consumers while the pressure fluid flows through a metering orifice, wherein the priority assigned to the first priority metering first metering orifice preceded by a pressure compensator and the subordinate second hydraulic consumer associated, second metering orifice downstream of a pressure compensator.
  • the pressure compensators constant pressure differences are maintained over the metering orifices with sufficient pressure medium supplied regardless of the load pressures of the hydraulic consumers, so that the hydraulic fluid consumers flowing pressure fluid quantity only depends on Publ tion cross section of the respective metering orifice.
  • the pressure medium source is usually an adjustable hydraulic pump, which is controllable in dependence on the highest load pressure such that the pressure in a supply line to a certain pressure difference above the highest load pressure.
  • the control circuit corresponds to a so-called load-sensing or load-sensing control (LS control).
  • LS control load-sensing or load-sensing control
  • From a LS-control or LS consumers are usually referred to when hydraulic consumers are controlled to which pressure medium flows via a metering orifice and an upstream pressure compensator, and when the pressure compensator detects the falling over the respective metering orifice pressure and keeps constant.
  • the pressure compensator is in the closing direction only by Pressure in front of the metering orifice and in the opening direction only by the load pressure of the respective hydraulic consumer and acted upon by a compression spring.
  • the control circuit corresponds to a so-called LUDV control.
  • the second metering orifice downstream pressure compensator is acted upon in the opening direction by the pressure after the second metering orifice and in the closing direction of a pending in a rear control chamber control pressure, which usually corresponds to the highest load pressure of all supplied by the same hydraulic pump hydraulic consumers.
  • LUDV control load-independent flow distribution
  • the correspondingly controlled hydraulic consumers are called LUDV consumers for short.
  • the LUDV control is a special case of a load-sensing or load-sensing control (LS control). Even with her, the highest load pressure is sensed and generated by the pressure medium source an inlet pressure, which is by a certain amount Ap over the highest load pressure.
  • the listed publication DE 197 03 997 A1 discloses a priority circuit between the LS consumer and one or more LUDV consumers, in which the LS consumer is primarily supplied with pressure medium.
  • a priority valve is provided which has a connected to a line section upstream of the first metering orifice first port and a second terminal connected to the Lastmelde gris and its valve member in the direction of opening the connection between the first port and the second port from the load pressure of the priority hydraulic consumer, so the LS consumer, and an additional force can be acted upon.
  • the valve member In the direction of closing, the valve member is acted upon by the pressure upstream of the metering orifice of the LS consumer - in a supply line or between the pressure compensator and the first metering orifice -.
  • This way becomes a priority Pressure medium supply of the LS consumer ensured.
  • the pressure upstream of the first metering orifice is controlled to a value that is at least an amount above the load pressure of the primary consumer, which corresponds to the additional force acting on the valve member of the priority valve.
  • the aim of the invention is based on the described prior art to provide a simpler and cheaper to produce hydraulic control device.
  • the present invention provides a hydraulic control device for a priority hydraulic consumer and one or more subordinate consumers.
  • the primary consumer is controlled via a first metering orifice, which is preceded by a (LS) pressure compensator.
  • the subordinate consumer is supplied via a second metering orifice, which is followed by a pressure compensator - in the manner of a LUDV control.
  • the peculiarity of the present invention is that a further control edge is provided on the valve piston of the pressure compensator of the priority consumer, which controls an injection of pressure medium from a supply line into a load-reporting line.
  • two control edges are present on the valve piston of this pressure balance.
  • the first control edge controls the pressure medium flow supplied to the first metering orifice in the sense of an individual pressure balance for the primary consumer.
  • the second control edge controls a flow cross-section between the inlet and the load-sensing line.
  • the pressure in the load-sensing line can be increased if the pressure difference dropping at the metering orifice of the 'primary consumer drops below a certain value. This causes an increase in the pressure level downstream of the second metering orifice and thus a reduction in the pressure medium flow supplied to the subordinate consumers.
  • pressure medium is available in sufficient quantity to the primary consumer.
  • the present invention takes advantage of the recognition that the pressure balance of the primary consumer and the control mechanism of a pressure increase in the load reporting line are controlled by the same pressure signals skillful to realize these two functionalities in a single, simple design valve. Compared to the conventional solution, a separate priority valve and thus material, space and cost is saved. Due to the smaller number of movable components, the control device according to the invention is also low maintenance.
  • the pressure difference arising at the metering orifice of the primary consumer can be kept virtually constant, regardless of the operating state, since this pressure difference is determined in each operating state by the control spring of the pressure compensator.
  • the pressure compensator of the priority consumer behaves like an individual pressure compensator and throttles the pressure medium supply so that a specific pressure difference prevails over the metering orifice of the primary consumer. If there is a supersaturation, the pressure in the load-sensing line is regulated by the second control edge, so that in turn the pressure difference at the metering orifice of the primary consumer corresponds to the pressure equivalence of this control spring.
  • control edges are arranged so that a direction of movement for opening the first flow cross section corresponds to the direction of movement for opening the second flow cross section.
  • control edges are formed on axially aligned in the same direction surfaces of the valve piston.
  • a particularly preferred embodiment provides that an opening of the second fürflußquefitess - ie a pressure medium supply to the load-sensing line - only then takes place when the hydraulic resistance at the first flow area is almost minimal.
  • the control mechanism of an increase in pressure in the load-sensing line only starts when the regulation of the flow rate through the pressure compensator - more precisely through the first flow cross-section - has reached the upper flow limit of its control range.
  • an unnecessary increase in the pressure level of the variable displacement pump and throttling of the subordinate LUDV consumers is avoided as long as the variable displacement pump still supplies sufficient pressure medium. If the control ranges of these two control mechanisms connect to each other and not or only slightly overlap, also always a stable, the respective load conditions clearly assigned operating state of the hydraulic control device according to the invention is always guaranteed.
  • a simple design of the pressure balance of the priority consumer results when it is designed as a slide valve with a valve bore and inlet chamber formed thereon and with two Trustkammem - a first connected to the metering orifice output chamber and a second connected to the Lastmelde effet output chamber.
  • the complexity of the pressure balance of the primary consumer can be reduced if one end face of the valve piston to the first output chamber, which is connected to the metering orifice, adjacent.
  • the pressure in the output chamber simultaneously acts as control pressure on the valve piston in order to pressurize it in the closing direction of the two flow cross sections.
  • a fluid path is formed in the valve piston, which connects a control pressure chamber formed on an end face of the valve piston with the first output chamber.
  • the fluid path comprises a bore which opens into the peripheral surface of the valve piston and which can be brought into overlap with the second output chamber.
  • the fluid path also serves as a pressure line to the control pressure chamber and as a flow path into the second output chamber.
  • a small flow cross-section is required between the supply line and the load-signaling line, and a quantity of pressure medium supplied / discharged to the control pressure chamber is likewise small.
  • a small diameter fluid path can be used.
  • the fluid pressure in the first output chamber largely corresponds to the fluid pressure in the inlet chamber. Therefore, fluid from a portion of the first output chamber can be easily supplied to the second output chamber instead of directly from the inlet chamber, and the described simple valve construction can be achieved.
  • valve piston Alternatively, a depression is present in the valve piston, which can be brought into coincidence with the inlet chamber and the second outlet chamber at the same time.
  • first flow cross section and the second flow cross section can be designed independently of each other.
  • Fig. 1 sucks a variable 10 with an adjustment. 11 pressure fluid from a tank 12 and it is in a system of supply lines.
  • a first hydraulic consumer 14 which is designed as a synchronous cylinder, and at least a second hydraulic consumer 15, which is a differential cylinder, supplied with pressure medium.
  • the direction and velocity of the synchronizing cylinder 14 is determined by a corresponding operation of a 4/3-way proportional valve 16 whose valve spool is spring-centered in a mid-position in which the four working ports and a control port 18 of the directional control valve 16 are locked.
  • a metering orifice 17 is opened differently wide depending on the way the valve spool is moved.
  • the control port 18 is connected downstream of the metering orifice with the flow to the synchronizing cylinder 14.
  • a control valve 45 is inserted, which has the function of a 2-way pressure compensator. Accordingly, the control valve 45 controls the flow area of a fluidic connection 20 between its inlet 46 and one of its outlets 23, ie between the inlet 13 and the inlet 19 Directional valve 16.
  • the valve piston 48 of the control valve 45 is in the direction of closing the connection 20 from the pressure upstream of a metering orifice 17 and in the direction of opening via a control line 61 from the pressure in the control port 18 of the directional control valve 16, ie the load pressure of the Gleichgangzylinders 14, and of a control spring 21 charged.
  • the force of the control spring 21 is designed so that its a pressure difference of z. B. 15 bar above the metering orifice 17 is equivalent.
  • the second hydraulic consumer 15 associated second pressure compensator 30 of a second metering orifice 31 downstream, for the directional control of the differential cylinder 15 is between the second pressure compensator 30 and the differential cylinder a directional control valve 32 is arranged, over which compared to the pressure drop at the metering orifice 31, no appreciable pressure drop occurs more when the differential cylinder 15 is actuated.
  • the metering orifice 31 and the control grooves necessary for directional control are formed in a known manner on the same valve spool, so that direction and speed control in each case go readily together.
  • the control piston 33 of the pressure compensator 30 is in the direction of opening the connection between the metering orifice 31 and the directional control valve 32 from the pressure to the metering orifice and in the direction of closing the connection of a prevailing in a rear control pressure chamber 34 control pressure and a weak compression spring 35, the pressure of z: B. only 0.5 bar equivalent is applied.
  • the front side of the control piston 33 is connected to the control pressure chamber 34 via a channel 36 extending in the control piston, wherein a check valve 37 opening towards the control pressure chamber is arranged in the channel 36.
  • the pressure compensator 30 and the directional control valve 32 for the second hydraulic consumer 15 can be connected to the system of the supply lines 13.
  • the control pressure chambers 34 of all pressure compensators 30 are connected to each other, so that in this Control pressure chambers the same pressure is pending.
  • the control piston 33 of the pressure compensators are trying to bring in an operation of a second hydraulic consumer in such a position in which sets at its front side only by the force of the compression spring 35 equivalent pressure difference higher pressure than in the control pressure chambers 34th
  • the control pressure chambers 34 are connected to a load signaling line 38, which leads to the adjustment 11 of the pump 10.
  • the load-signaling line 38 is furthermore connected to the tank 12 via a current regulator 55. About this current regulator the load-sensing line 38 is relieved of pressure, if none of the hydraulic load is operated.
  • the first hydraulic consumer 14 is to be supplied with priority prior to the second hydraulic consumer 15 with pressure medium.
  • a second controllable connection 22 is provided in the control valve 45.
  • the connection 22 is formed as a diaphragm with proportionally controllable fürftussquerexcellent between the input 46 and an output 47. The latter is connected to the load-signaling line 38.
  • valve piston 48 of the control valve 45 is in the closing direction of a pressure upstream of the metering orifice 17 and in the direction of opening of the through Control line 61 zoom supplied load pressure of the primary consumer 14 and the control spring 21 acted upon.
  • valve housing 70 In the valve housing 70, a valve bore 71 is present. In this bore, the valve piston 48 is slidably mounted. An inlet chamber 72 and two outlet chambers 73 and 74 adjoin the valve bore. The inlet chamber is connected to the port 46 designed as a bore and thus to the supply line 13. The outlet chamber 73 communicates with the outlet 23, ie with the metering orifice 17. The output chamber 74 opens via the connection 47 in the load-signaling line 38.
  • the controllable fluidic connection 20 is achieved via a radially recessed portion 76 of the valve piston 48.
  • the control edge 77 is formed on the valve piston 48.
  • the control edge 77 defines a first flow area between it and a housing web 78 'formed between the inlet chamber 72 and the outlet chamber 73.
  • the fluidic connection 22 is formed by a recess 78 in the peripheral surface of the valve piston 48.
  • This recess 78 may be e.g. be an axial groove or a radial graduation of the valve piston.
  • a control edge 79 delimiting the depression 78 in the direction of the outlet chamber 74 forms a second controllable and closable flow cross-section with the outlet chamber 74.
  • a control pressure chamber 50 is connected to the control line 61, which carries the load pressure of the priority consumer 14.
  • the pressure in the control pressure chamber 50 acts on the valve piston 48 in the opening direction of the fluid connections 20 and 22.
  • the pressure prevailing in the control pressure chamber 49 acts.
  • the control pressure chamber 49 is connected via a formed in the valve piston 48 fluid passage 75 with the radially recessed portion 76 and thus the output chamber 73 in fluid communication.
  • the control edge 79 is arranged so that the connection 22 opens only when the flow cross section at the control edge 77 is already almost maximum, ie when the pressure drop ⁇ p DW at the control edge 77 has a value ⁇ p DW . has reached close to a minimum.
  • the value ⁇ p DW is arranged so that the connection 22 opens only when the flow cross section at the control edge 77 is already almost maximum, ie when the pressure drop ⁇ p DW at the control edge 77 has a value ⁇ p DW . has reached close to a minimum.
  • the value ⁇ p DW is arranged so that the connection 22 opens only when the flow cross section at the control edge 77 is already almost maximum, ie when the pressure drop ⁇ p DW at the control edge 77 has a value ⁇ p DW . has reached close to a minimum.
  • the value ⁇ p DW is arranged so that the connection 22 opens only when the flow cross section at the control edge 77 is already almost maximum, ie when the pressure drop
  • control pressure difference ⁇ p remains constant at the value set by the control spring of the pump adjustment 11, e.g. 20 bar.
  • the pending in the supply line 13 pressure sozulange greater than the sum of the load pressure of the priority consumer 14 and the pressure equivalence of the control spring 21 is, via control edge 77, a pressure drop Ap DW for controlling the supply of the primary consumer. Due to the pressure drop ⁇ p DW , a pressure surplus existing from the point of view of the primary consumer 14 in the supply line 13 is throttled.
  • the pressure p 38 in the load-sensing line corresponds to the highest load pressure of the subordinate consumers, hereinafter referred to as p LUDV .
  • the second control edge 79 opens the flow cross-section of the connection 22. This increases the pressure p 38 in the load-sensing line 38 to values greater than p LUDV . If the pressure in the supply line 13 (p 38 + ⁇ p) was previously dependent only on the load pressure p LUDV of the subordinate consumers, the supply pressure (p 38 + ⁇ p) is now determined by the load pressure p LS of the priority consumer 14. The regulation of the supply line pressure (p 38 + ⁇ p) takes place with the aid of the control edge 79 and the feedback via the adjustment 11.
  • the pressure of the load-sensing line 38 increase to the inlet pressure (p 38 + ⁇ p) and completely suppress the supply of the subordinate consumer 15 by means of the pressure compensator 30.
  • several subordinate consumers 15 can be respectively to be respectively.
  • the inlet pressure (p 38 + ⁇ p) in turn adjusts according to Equation 3 to a value which is substantially higher than the load pressure of the primary consumer 14 by the pressure equivalence p 21 'of the control spring 21.
  • FIG. 3A shows a control valve 85, which represents a modified embodiment of the control valve 45.
  • a symbol representation of the control valve 85 is in FIG. 3B shown.
  • the control valve 85 differs only by the valve piston 88 of the control valve 45.
  • the valve piston 88 has a radially recessed piston portion 76. From this piston portion is a fluid channel 75 goes out, which opens at an end face of the valve piston 88 in the control pressure chamber 49 ,
  • the bore 86 forms a control edge 89 for controlling a flow cross section at the output chamber 74.
  • this formed between the control edge 89 and the valve housing 70 opening cross-section opens only when the hydraulic resistance or the pressure drop .DELTA.p DW at the control edge 77 has already reached a value ⁇ p DW * near the minimum value.
  • the pressure of the pressure medium which is supplied via the fluid path 75 when opening the control edge 89 of the radially recessed piston portion 76 corresponds approximately to the pressure in the input port 46.
  • the pressure in the Lastmeldetechnisch 38 bis be increased almost to the pending at the input port 46 supply pressure.
  • FIG. 4 Another embodiment of a control valve 95, which may take the place of the control valve 45 or 85 is in FIG. 4 outlined.
  • the symbol representation of the control valve 95 corresponds to the FIG. 3B .
  • a valve bore 91 is provided in the valve housing 90 of the control valve 95.
  • an inlet chamber 92 and two outlet chambers 93 and 94 are arranged on the valve bore 91.
  • the chambers 92, 93 and 94 are fluidly connected to respective ports 46, 47 and 23, as in FIGS FIG. 4 shown.
  • a cylindrical valve piston 96 is movably guided.
  • the valve piston 96 has an axially extending blind hole 97 open in the direction of the outlet chamber 93. From the peripheral surface of the valve piston 96, two radially extending holes 98 and 99 abut the blind hole 97.
  • the bore 98 can be brought into overlap with the inlet chamber 92.
  • a fluid connection is created by the inlet connection 46 via the bore 98, the blind bore 97, the outlet chamber 93 and the outlet connection 23.
  • the control edge 100 which controls the flow cross-section of this connection, is the circumferential surface-side edge of the bore 98.
  • a fluid connection from the inlet connection 46 to the outlet connection 47 is established via the bore 98, the blind bore 97, the bore 99 and the outlet chamber 94.
  • the relevant control edge 101 is the circumferential surface side edge of the bore 99.
  • the bore 99 is arranged so that it only overlaps with the output chamber 94, when the controlled at the bore 99 flow cross-section only a small hydraulic resistance / pressure drop ⁇ p DW * caused. As a result, the pressure in the load-signaling line 38 can be increased to almost the inlet pressure at the inlet connection 46.
  • control pressure chamber 50 At one of the blind hole 97 facing away from the end face of the valve piston 96 limits this formed in the valve housing 90 control pressure chamber 50. This is connected to the control line 61, the Load pressure of the priority consumer 14 leads. The pressure prevailing in the control pressure chamber 50 acts in the opening direction of the controlled through the holes 98 and 99 compounds. In addition, the control spring 21 arranged in the control pressure chamber 50 acts in the opening direction. In the closing direction of the valve piston 96 is acted upon directly by the pending in the output chamber 93 pressure, since the valve piston 96 with its end face in which the blind hole 97 opens, adjacent to the output chamber 93.
  • control valve 95 On the one hand by this embodiment of the control valve 95, a very low pressure drop ⁇ p DW * at the bore 98 achievable, on the other omitted by the arrangement of the output chamber 93 at the front end of the valve piston 96, a separately formed control chamber and an internally or externally guided to this control line ,
  • FIG. 5 shows a further embodiment of the hydraulic control device according to the invention.
  • the execution after Fig. 5 is largely the same after execution Fig. 1 , Different from the execution after Fig. 1 is that now the control line 61, which leads from the control port 18 of the directional control valve 16 to the control valve 45, via a located in a bypass line 62 check valve 63 is also connected to the load signaling line 38.
  • the check valve 63 locks from the load-signaling line 38 to the channel 61, that is, to the control port 18 of the directional control valve 16.
  • a check valve 64 is also arranged between the second connection 47 of the control valve 45 and the load-receiving line 38. This locks to port 47.
  • Fig. 1 finds a change in the control mechanism of the control valve 45 takes place even if in sufficient quantity conveyed pressure medium, as described above, if the load pressure p LS of the priority consumer 14 by the subordinate consumer predetermined inlet pressure (p LUDV + ⁇ p) minus the pressure equivalent p 21 of Control spring 21 exceeds (the pressure drop ⁇ p DW * at the control edge 77 is negligible). If the primary consumer becomes load-bearing in this sense, the control valve loses its functionality as a LS pressure compensator. This is replaced by the mechanism of controlling the pressure in the load-sensing line 38.
  • Fig. 5 In the execution after Fig. 5 is carried out at sufficiently promoted pressure fluid quantity and load-carrying priority hydraulic consumers 14 of the load pressure gravel hydraulic consumer via the check valve 63 in the load reporting line 38.
  • the pressure in the supply line 13 is thus the Regeleldruckdiflerenz .DELTA.p of the variable displacement pump 10 above the load pressure of the hydraulic consumer 14.
  • the control valve 45 has in this case the function of a LS-pressure compensator and throttles the metering orifice 17 supplied pressure medium flow through the first control edge 77th
  • the pressure difference across the pressure compensator 17 corresponds to the pressure equivalent p 21 of the control spring 21.
  • the check valve 64 prevents a pressure medium flow from the hydraulic consumer 14 via the check valve 63 in the system of the supply lines, if z. B. at the beginning of an actuation of the pressure in the supply lines is not above the load pressure.
  • the check valve 64 may also be omitted if the port 47 of the control valve 45 is connected to the check valve 63 so that the check valve 63 to port 47 blocks out.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
EP06828803A 2005-09-30 2006-09-29 Hydraulische steuervorrichtung Not-in-force EP1934487B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102005047310A DE102005047310A1 (de) 2005-09-30 2005-09-30 Hydraulische Steuervorrichtung
PCT/EP2006/009480 WO2007039249A1 (de) 2005-09-30 2006-09-29 Hydraulische steuervorrichtung

Publications (2)

Publication Number Publication Date
EP1934487A1 EP1934487A1 (de) 2008-06-25
EP1934487B1 true EP1934487B1 (de) 2011-07-27

Family

ID=37671178

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06828803A Not-in-force EP1934487B1 (de) 2005-09-30 2006-09-29 Hydraulische steuervorrichtung

Country Status (7)

Country Link
US (1) US7870729B2 (zh)
EP (1) EP1934487B1 (zh)
CN (1) CN101278132B (zh)
AT (1) ATE518064T1 (zh)
DE (1) DE102005047310A1 (zh)
ES (1) ES2367450T3 (zh)
WO (1) WO2007039249A1 (zh)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8353157B2 (en) * 2009-08-06 2013-01-15 Cnh America Llc Open center hydraulic system
DE102012218427A1 (de) * 2012-10-10 2014-04-10 Robert Bosch Gmbh Hydraulische Steueranordnung für einen hydraulischen Verbraucher und hydraulische Steuereinheit mit einer Mehrzahl derartiger Steueranordnungen
DE102014004337B4 (de) 2013-03-28 2023-04-27 Aebi Schmidt Deutschland Gmbh Kommunalfahrzeug sowie Verfahren zur Einstellung von Pumpenausgangsdrücken einer Verstellpumpe
EP4019786B1 (en) * 2020-12-28 2023-11-22 Danfoss Power Solutions (Zhejiang) Co. Ltd Load-sensing multi-way valve work section

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4043419A (en) * 1976-06-04 1977-08-23 Eaton Corporation Load sensing power steering system
US4663936A (en) * 1984-06-07 1987-05-12 Eaton Corporation Load sensing priority system with bypass control
US5077972A (en) * 1990-07-03 1992-01-07 Caterpillar Inc. Load pressure duplicating circuit
FR2694964B1 (fr) 1992-08-21 1994-11-04 Rexroth Sigma Circuit hydraulique de commande d'un distributeur du type à division de débit indépendant de la charge.
DE4235709A1 (de) 1992-10-22 1994-04-28 Linde Ag Hydrostatisches Antriebssystem
DE19703997A1 (de) * 1997-02-04 1998-08-06 Mannesmann Rexroth Ag Hydraulischer Steuerkreis für einen vorrangigen und für einen nachrangigen hydraulischen Verbraucher
JPH11115780A (ja) * 1997-10-15 1999-04-27 Komatsu Ltd 作業車両用ステアリングポンプの容量制御方法および装置
DE10119276B4 (de) 2001-04-20 2009-12-10 Bosch Rexroth Aktiengesellschaft Hydraulischer Steuerkreis
ITMO20020332A1 (it) * 2002-11-15 2004-05-16 Studio Tecnico 6M Srl Circuito fluidodinamico per la alimentazione di utenze primarie ed ausiliarie con priorita' predefinite.

Also Published As

Publication number Publication date
CN101278132B (zh) 2012-08-08
US7870729B2 (en) 2011-01-18
EP1934487A1 (de) 2008-06-25
ES2367450T3 (es) 2011-11-03
DE102005047310A1 (de) 2007-04-05
US20080256940A1 (en) 2008-10-23
ATE518064T1 (de) 2011-08-15
CN101278132A (zh) 2008-10-01
WO2007039249A1 (de) 2007-04-12

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