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
  • 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
  • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative 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
  • 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
• • 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
  • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
  • F15B21/04—Special measures taken in connection with the properties of the fluid
  • F15B21/047—Preventing foaming, churning or cavitation
• • 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
  • F15B2211/50—Pressure control
  • F15B2211/505—Pressure control characterised by the type of pressure control means
  • F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
  • F15B2211/50545—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using braking valves to maintain a back 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
  • F15B2211/50—Pressure control
  • F15B2211/505—Pressure control characterised by the type of pressure control means
  • F15B2211/50554—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure downstream of the pressure control means, e.g. pressure reducing 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
  • F15B2211/50—Pressure control
  • F15B2211/52—Pressure control characterised by the type of actuation
  • F15B2211/528—Pressure control characterised by the type of actuation actuated by fluid 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
  • F15B2211/50—Pressure control
  • F15B2211/555—Pressure control for assuring a minimum pressure, e.g. by using a back pressure 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
  • F15B2211/50—Pressure control
  • F15B2211/565—Control of a downstream 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
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
  • F15B2211/7135—Combinations of output members of different types, e.g. single-acting cylinders with rotary motors
• • 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
  • F15B2211/80—Other types of control related to particular problems or conditions
  • F15B2211/86—Control during or prevention of abnormal conditions
• • 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
  • Y10T137/2496—Self-proportioning or correlating systems
  • Y10T137/2544—Supply and exhaust type
  • Y10T137/2554—Reversing or 4-way valve systems
• • 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
  • Y10T137/2496—Self-proportioning or correlating systems
  • Y10T137/2559—Self-controlled branched flow systems
  • Y10T137/2574—Bypass or relief controlled by main line fluid condition
  • Y10T137/2605—Pressure responsive
  • Y10T137/263—Plural sensors for single bypass or relief valve
  • Y10T137/2632—Sensors interconnected by timing or restrictive orifice
• • 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
  • Y10T137/2496—Self-proportioning or correlating systems
  • Y10T137/2559—Self-controlled branched flow systems
  • Y10T137/265—Plural outflows
  • Y10T137/2657—Flow rate responsive
• • 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
  • Y10T137/2496—Self-proportioning or correlating systems
  • Y10T137/2559—Self-controlled branched flow systems
  • Y10T137/265—Plural outflows
  • Y10T137/2668—Alternately or successively substituted outflow
  • Y10T137/2678—Four port reversing valve
• • 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
  • Y10T137/2496—Self-proportioning or correlating systems
  • Y10T137/2708—Plural sensors
• • 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]
  • Y10T137/7904—Reciprocating valves

Definitions

• the invention relates to a control device for hydraulic consumers with at least one control valve for controlling a feed line for the respective hydraulic consumer and with a tank return.
• this fluid is supplied via an additional feed system in each endangered pressure line as a feed line.
• the pertinent feed only succeeds if the feed pressure applied via this feed system is greater than the pressure in the endangered feed line plus the sum of all pressure drops at the throttle points used from the feed line to the endangered line.
• an additional pump system is often encountered in hydrostatic drives.
• a more cost-effective option is to back up the fluid reflux to the tank as a pressure chamber in conventional valve control systems via a so-called tank pretensioning valve as the control valve and then remove the required feed volume from this pressure space.
• the permanent energy loss, resulting from the additional borrowed pump delivery and the set dynamic pressure or to the back pressure basically reduced working capacity of the hydraulic consumers.
• fluidic pressure medium can then escape via the after-suction valve to the tank without any great resistance, and in the braking phase the after-suction valve is automatically biased to a higher opening pressure so that an extreme feed into the hydrostatic drive system can be dispensed with due to the increased secondary pressure level.
• an additional pump system in the manner of an auxiliary pump to maintain a certain inlet-side pressure levels;
• the known solution with a control valve in two-piston design consuming and therefore expensive to manufacture.
• a commercial vehicle hydraulics is known, in particular for a refuse vehicle, with at least one hydraulic circuit to the various actuators to perform various functions, such as opening the rear part, lifting and tilting a refuse container, etc., are connected.
• the known solution on one of a motor or coupled to this power take-off of the utility vehicle driven pump to promote Hydraultköl in the hydraulic circuit.
• the pump is constructed such that its delivery rate is at least partially controllable independently of the speed of the engine.
• a hydraulic system is known from DE 197 35 482 A1 with a differential cylinder with piston rod and piston, which separates a piston rod side pressure chamber and a piston rod downstream pressure chamber from each other.
• the two pressure chambers of the differential cylinder can be alternately connected to a pressure medium source and to a tank.
• the piston rod-side pressure chamber can be connected to the piston rod-side pressure chamber of the differential cylinder by means of a rapid traverse valve.
• the present invention seeks to further improve the known solutions to the effect that in any case, damaging cavitations are reliably prevented in functionally reliable, energy-saving and cost-effective manner.
• This object is achieved by a drive device having the features of patent claim 1 in its entirety.
• control valve is connected to an additional supply line and is designed as a priority valve that receives the feed line has the advantage of a fluid supply to the tank return, a kind of sensor circuit is realized, which checks whether depending on the load situation There is a need for feed-in power at all at the hydraulic consumer.
• the control valve for the control device according to the invention is constructed in the manner of a priority valve, which as a so-called.
• Tank preload valve of the addressed feed line is the preference before the free tank return.
• a further second feed line can be provided for additional and direct supply of the feed line.
• the further supply line in the control valve via a control edge of the valve piston can be influenced and can be shut off by the control stroke of a control spring of the control valve so that there is an interruption of the connection in the feed line.
• the further second feed line begins in a channel of the pressure supply and is determined via a defined throttle point in their flow behavior.
• FIGS. 6 is a perspective view of the cut control valve according to FIGS. 2 to 5.
• the illustrated working cylinder 10 may, for example, be part of a working machine in the form of a wheel loader or the like in order to raise and lower a working tool in the form of a conventional lifting mechanism with a blade.
• the hydraulic motor 12 drives, for example, a mechanical slewing gear 16, which is based on an inertia J.
• hydraulic motors 12 for example, hydraulic lifts can be actuated, running gears of working machines, such as forklifts, driven and the like more.
• the possibilities of use both for hydraulic power cylinders and for hydraulic motors are almost unlimited.
• both the working movement of the piston rod unit of the working cylinder 10 and the respective rotary Direction for the hydraulic motor 12 reversible. It applies to the hydraulic motor 12 that when driving the slewing gear 16 in one direction he experiences a pressing load when accelerating, whereas when braking a pulling load is created because the inertial mass (moment of inertia J) of the turning factory 16 continues.
• the situation on the working cylinder 10 is comparable if a load has to be pressed in one direction and pulled in the other opposite direction for a retraction movement.
• the inlet pressure can then quickly drop to the cavitation pressure and below, what to prevent because of the harmful effects. This purpose is served by the control device, which is to be shown in more detail.
• control device has a control valve 18, which, inter alia, serves to control a feed line TRe 8 for the respective hydraulic consumer 10, 12. Diametrically opposite to the output-side feed line TR "* is connected to the control valve 18 of a further tank return TRO on the input side. Another output of the control valve 18 is connected to an additional feed line TR and the control valve 18 is designed as a priority valve, that the feed line TRe 8 receives the benefit of a fluid supply to the tank return TRO.
• the pressure supply p is in turn connected via a throttle Di on the input side of the control valve 18 and in a side branch 20, the pressure supply p opens on the input side of two further control valves 22,24, the one Control valve 22 on the output side with its fluid connections in each case with the Nutzan Whyn Ai, Bi of the hydraulic cylinder 10 is in communication and the second further control valve 24 is connected to the Nutzan say A2, B2 of the hydraulic motor 12 accordingly.
• the respective valve 22,24 is also the input side in fluid-carrying connection with the feed line TR and the two leading to the respective user terminals Ai, Bi, A2, B2 outputs are each connected via a fluid line to the feed line TRe 8 .
• check valves 26,28 are connected, wherein the check valve 28 which leads respectively to the Nutzanschluß Bi, B2, should be provided with a pressure limiting function. Furthermore, all the check valves 26, 28 open in the direction of their respectively assignable useful connections Ai, Bi, A2, B2.
• the other second control valves 22,24 are formed in the type of 4/3-way valves and shown in its middle unactuated position, in which the respective input side is separated from the output side.
• the respective 4/3-way valve can be actuated hydraulically or electro-hydraulically in the usual way via opposite control connections ai, bi as well as a2, b2.
• the respective 4/3-way valves can also be optionally replaced by others Replace valve designs and in addition to the illustrated cylinder 10 and the hydraulic motor 12 can occur more consumers of the same kind or different types.
• the control block 14 can also serve only to control a hydraulic consumer 10 or 12.
• a check valve RV is connected, which opens in the direction of the feed line TRe 8 .
• the control valve 18 has the further an internally extending second feed line 30, which is influenced by a second throttle D2. The details of this will be explained with reference to the sectional views of Fig.2ff.
• the valve piston 32 of the control valve 18 is supported against a control spring 34 in the form of a compression spring.
• a permanently throttled discharge line 36 is connected, which preferably has a further defined throttle point D2 '.
• the relief line 36 further opens to the control side 38 of the control valve 18, which acts opposite to the control spring 34 on the valve piston 32.
• the control block 14 is designed in the manner of a sensor circuit which "senses" whether there is a demand for feed-in current for the respective consumer 10, 12. Only when the demand in question is "felt” does the free tank return TRO come on accumulated the required pressure height required.
• the two independent return lines are used in the control block 14. One is in this case formed by the feed line TR for the control valve 18, the other is the feed line TRe 8 to the check valves 26,28 designed as feed valves.
• the control valve 18 thus forms a kind of tank pilot valve and is designed as a priority valve in such a way that it gives preference to the feed line TRe 8 from the fluid supply before the free tank return TRO.
• the addressed sensor circuit relieves the tank return TRO, SO no supply requirement is reported.
• the tank return TRO is throttled to a constructively predetermined height, which is essentially determined by the spring force of the control spring 34.
• the control valve 18 continues to regulate the constructively set pressure in the feed line TRe 8 by throttling the outflow cross section to the free tank return TRO, thereby simultaneously raising the pressure in TR above those in the feed line TReg and now through the fluid medium the check valve RV must flow into the feed line TRe 8 .
• the respectively effective pressure surface on the valve piston 32 of the control valve 18 designed as a pressure compensator is used.
• the control valve 18 is preferably designed as a 4/3-way proportional valve to form the pressure compensator.
• the control valve is shown in more detail in the following figures with reference to various working positions.
• 2 corresponds to the circuit diagram of the valve according to FIG. 6, that is to say viewed in the direction of FIGS. 2 and 6, the control or valve piston 32 guided within the valve housing 44 is in its extreme left switching position he on the left side abuts a wall of the valve housing 44.
• the valve housing 44 a plurality of widened in the circumferential annular spaces 46,48,50,52 and 54 are present.
• the last-mentioned annular space 54 accommodates the control spring 34 designed as a compression spring.
• the pressure supply p flows from left to right in the first annulus 46, the feed line TReg and the other second annulus 48, the pressure supply p is connected to the throttle point D1.
• the feed line TR opens and to the subsequent fourth annulus 52, the free tank return TRO is connected.
• the individual annular spaces 46, 48, 50, 52 and 54 are essentially fluid-tightly separated from one another via piston segments 56, 58, 60 and 62.
• the pertinent piston segments 56, 58, 60 and 62 are widened in diameter relative to the other diameter profile of the valve piston 32 with the formation of effective annular piston surfaces.
• FIG. 2 and 6 for the valve piston 32 individual with a, b, c designated overlaps of the valve piston 32 are shown in the valve housing 44, wherein in the pertinent operating position a ⁇ b ⁇ c and with respect to said left stop position is the free travel x for the valve piston 32 in the possible direction of travel to the right equal to 0.
• the valve piston 32 is penetrated along its longitudinal axis 66 by a longitudinal bore 68, which opens out on both sides of the valve piston 32 to the outside, ie in the first annular space 46 and in the fifth annular space 54th
• a first transverse bore 70 is present between the first piston segment 56 and the second piston segment 58, which opens into the second annular space 48 in the working position shown in FIG. 2 and otherwise communicates with the longitudinal bore 68 in the form of a longitudinal channel ,
• a second transverse bore 72 of larger diameter emerges as part of the longitudinal bore 68 in the direction of the valve housing 44 from the second piston segment 58.
• a third transverse bore 74 is provided which opens into the fourth annular space 52 between the piston segments 60 and 62.
• each transverse bore 70,72,74 also include a plurality, in particular four mutually perpendicular channel sections.
• the transverse boring arrangements following one another in the longitudinal planes can be arranged adjacent to one another by 90 ° offset from each other.
• the second throttle D2 is arranged within the longitudinal bore 68 in the piston section between the second piston segment 58 and the third piston segment 60.
• the valve piston 32 is designed to extend in steps at its right end as viewed in the direction of FIG.
• the outer diameter of all piston segments is the same; however, the effective piston surfaces 64 are different in diameter from each other; however, the mutually adjacent piston surfaces 64 of two piston segments 56, 58, 58, 60 and 60 and 62 have the same effective piston surface 64.
• the throttles D1 and D2 should be closed in the sense of an intellectual assumption.
• the unpressurized state then presses the valve spring 34, the control piston 32 against the mechanical stop in the form of an inner housing wall of the valve housing 44.
• the fluid-conducting connection between TR and TRO is shut off.
• the hydraulic pump is turned on and fluid pressure p is present in the second annular space 48, no hydraulic resistance is present in the feed channel TReg, with the result that the working medium flowing in the return line via the valve RV depressurized via the feed valves 26, 28 to the hydraulic consumers 10 , 12 arrived.
• The- This working condition prevails when pulling loads. If there are no more pulling loads, then the feed valves 26,28 close and no volume flow flows anymore.
• the pressure in TRe 8 and TR increases.
• the throttle D1 should now be opened.
• the TR, g fluid leading channel as Einspeiselei- device is then supplied not only via the valve RV from TR side, but also via the throttle D1, starting from a high pressure level, for example in the form of the pump supply pressure p. If now no pulling loads occur, then the valve piston 32 again moves in the direction of the figures to the right against the spring 34 and it comes within the valve to a fluid-carrying connection of TR to the non-return TRO. The consequence of this is that the pressure in TR decreases.
• the valve RV closes because the feed line TRe 8 is additionally fed via the throttle D1 and no volume flow flows. Therefore, the pressure in the supply line ⁇ Re g remains at a level which corresponds to the amount of the control spring 34.
• control or valve piston 32 can then run completely against the control spring 34, without the feed pressure being withdrawn from TR. Therefore, with the connection TR fully open, the pressure at TR decreases to the level of TRO. If the valve piston 32 ran against the spring 34 until the mechanical stop, then the pressure in the feed line TRe 8 would have run up to the level of the inlet pressure in the second feed line 30.
• the respective feed valves 26, 28 would then optionally open and feed undesirably into consumer ports Ai, Bi, A2, E? 2.
• the amount of control oil consumption is determined by the magnitude of the force of the control spring 34 and the throttling action of D2.
• Typical design values vary between a compressive preload of 10 bar, combined with D2 equal to 0.8 mm and a compressive preload of 7 bar, combined obtained from two series-connected restrictors of 0.6 mm as D2. This can be varied by interpretation, the control oil consumption of 1 l / min to 0.34 l / min easily.
• the associated energy losses are then dependent on the current pump pressure p, which supplies the second feed line 30 with. At a mean pump pressure of 200 bar then occur losses of 0.3 KVV or 0.1 KVV.
• the tank biasing valve in the form of the control valve 18 can carry its stroke until a connection feed line TRe 8 opens to Spetse effet TR, feed line TR is already unthrottled connected to the free tank return TRO.
• the working capacity of the hydraulic consumers 10, 12 can be increased with the control device described, as long as no feed state is present.
• An increase in pressure by 7 to 10 bar readily possible, so that energy is saved in this respect to this enabled dynamic pressure.
• the working capacity of the hydraulic consumers is, for example, increased by 7 to 10 bar when there is no feed state. Energy is then saved in the scope of the released dynamic pressure of 7 to 10 bar.
• a typical example is a small excavator with a mean volume flow of 50 l / min and 7 bar back pressure in the feed channel.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Fluid-Pressure Circuits (AREA)
• Control Of Transmission Device (AREA)
• Means For Warming Up And Starting Carburetors (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Related Child Applications (2)

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• 2006
  • 2006-12-22 DE DE102006061305A patent/DE102006061305B3/de not_active Expired - Fee Related
• 2007
  • 2007-10-26 EP EP20070819343 patent/EP2126370B1/fr not_active Not-in-force
  • 2007-10-26 AT AT07819343T patent/ATE550552T1/de active
  • 2007-10-26 US US12/448,417 patent/US8443827B2/en not_active Expired - Fee Related
  • 2007-10-26 WO PCT/EP2007/009295 patent/WO2008083772A1/fr active Application Filing
  • 2007-10-26 EP EP20110010098 patent/EP2441966B1/fr not_active Not-in-force
  • 2007-10-26 DK DK07819343T patent/DK2126370T3/da active
  • 2007-10-26 DK DK11010099T patent/DK2441967T3/da active
  • 2007-10-26 DK DK11010098T patent/DK2441966T3/da active
  • 2007-10-26 EP EP20110010099 patent/EP2441967B1/fr not_active Not-in-force

Non-Patent Citations (1)

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