CN1033052C - Regulator for a variable displacement pump - Google Patents

Regulator for a variable displacement pump Download PDF

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Publication number
CN1033052C
CN1033052C CN94102775A CN94102775A CN1033052C CN 1033052 C CN1033052 C CN 1033052C CN 94102775 A CN94102775 A CN 94102775A CN 94102775 A CN94102775 A CN 94102775A CN 1033052 C CN1033052 C CN 1033052C
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CN
China
Prior art keywords
pump
valve
regulator
working pressure
servopiston
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.)
Expired - Fee Related
Application number
CN94102775A
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Chinese (zh)
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CN1094794A (en
Inventor
金荣国
金泰钟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hyundai Doosan Infracore Co Ltd
Original Assignee
Daewoo Heavy Industries Ltd
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Filing date
Publication date
Application filed by Daewoo Heavy Industries Ltd filed Critical Daewoo Heavy Industries Ltd
Publication of CN1094794A publication Critical patent/CN1094794A/en
Application granted granted Critical
Publication of CN1033052C publication Critical patent/CN1033052C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/14—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/002—Hydraulic systems to change the pump delivery
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26—Control
    • F04B1/30—Control of machines or pumps with rotary cylinder blocks
    • F04B1/32—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block
    • F04B1/324—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block by changing the inclination of the swash plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/08—Regulating by delivery pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2201/00—Pump parameters
    • F04B2201/12—Parameters of driving or driven means
    • F04B2201/1204—Position of a rotating inclined plate

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Reciprocating Pumps (AREA)
  • Rotary Pumps (AREA)

Abstract

A regulator for a variable displacement pump is provided with a hydraulic servo controller capable of controlling the displacement volume of the pump and accomplishing a feedback function depending upon the working pressure from the pump, an effective spring force and a pilot pressure.

Description

The regulator that is used for variable displacement pump
The present invention relates to a kind of regulator that is used for variable displacement pump, particularly a kind of such regulator, it is provided with hydraulic servo controller, discharge amount that can control pump, and with feedback function, this function depends on the working pressure of pump, effectively spring force and pilot pressure, thereby regime flow and cutting down the consumption of energy.
Variable displacement pump commonly used comprises the regulator of the device of the wobbler angle that adopts a control pump.For example Japanese publication: 89-116294, it has disclosed a kind of regulator, comprises a valve body; Be used for the device of wobbler angle of control pump; A pilot operated directional control valve, it is used for limiting the position that first valve pocket is provided the working pressure fluid, and one limits the position of sealing first valve pocket and limits the position of discharging induced pressure from first valve pocket; The reaction lever that one end of selector valve is linked to each other with the servopiston of control gear; The first guiding guiding valve that can be moved by the working pressure of pump is used for the horsepower of control pump; One can be by pilot pressure, comprising the second guiding guiding valve that moves of tank pressure be used for the flow of control pump; Be used for selecting an effect of first or second guiding guiding valve reaction lever with a linking mechanism, to reduce emission flow.
Yet the linking mechanism of its regulator has made whole structure and complex structure.Have again, in the control procedure of flow, the influence that the flow of pump is changed by the tank pressure of hydraulic system probably, this just is difficult to obtain and keeps and give fixed flow indicator.In addition, the regulator deficiency also lacks cutout control and removes the control of cutout, and this just can't cause the loss of energy by unwanted flow.
Therefore, an object of the present invention is to provide a kind of regulator that is used for variable displacement pump, it has cancelled linking mechanism, and is simple in structure.
Another object of the present invention provides a kind of regulator that is used for variable displacement pump, its eliminated hydraulic system tank pressure influence and can realize stable flow rate control.
A further object of the invention provides a kind of regulator that is used for variable displacement pump, and it can during greater than predetermined value, have cutout control, to reduce energy loss in the working pressure of pump.
The above-mentioned purpose with other of the present invention is that the angle that proposes a kind of wobbler with by changing pump is controlled the variable displacement pump that the regulator of fluid flow combines, and it comprises: a generation fluid flow pump; A valve body that is communicated with pump; A servopiston that pivotally is installed on the pump wobbler, piston has two-part, and each part has different diameters, and both can be along moving in first and second valve pockets that form in the valve body; One can working pressure effect by pump under, along the multi-level piston that moves in first and second piston chamber in valve body; One has the servo guiding valve that is used to change flow direction, and the controlling rod that can move along the servopiston axis; A servo sleeve that is communicated with servo guiding valve, it is used for limiting a point midway, and position of supplying with the second valve pocket working pressure fluid and one discharge the position of working pressure fluid in the fuel tank; A cut-off slide valve that is communicated with servo sleeve, be used for limiting the working pressure of supplying with self-pumping fluid to the second valve pocket the position and discharge the position of working pressure fluid from second valve pocket to servo sleeve; Be used for to servopiston that is isolated from each other and the biased device of controlling rod.
That is to say that the present invention has gone out a kind of regulator that is used for variable displacement pump, this regulator to make it the controlling fluid flow that is produced by pump, is characterized in that described regulator comprises by means of the angle that changes wobbler: the threshold body that is connected with fluid with pump; Be journaled on the wobbler and be provided with two-part servopiston, this each several part is to have different mutually diameters, is to move along first and second valve pockets that are formed in the valve body;
Can have servo guiding valve along the controlling rod that the servopiston axis moves, to be used for changing the direction of the fluid stream that comes self-pumping;
Multi-level piston contacts with controlling rod and moves along first and second piston chamber that are formed in the valve body by means of the working pressure of pump;
Servo sleeve can be contained in the controlling rod rear with restoring and be connected with servo guiding valve fluid making it to be used for limiting a point midway, and one supplies to the position of second valve pocket and a position that working pressure is discharged into fuel tank with working pressure from pump;
Cut-off slide valve that is connected with the second valve pocket fluid and servo sleeve supply to the position of second valve pocket and the position that working pressure from second chamber be discharged into servo sleeve with working pressure from pump to make it to be used for limiting;
The cutout piston that is connected with cut-off slide valve can move along the first and second cutout piston chamber, and this first Room and pump are linked up, and this second Room and pilot conduits are linked up.
It is spaced being used for a pair of spring of bias voltage controlling rod and servopiston, and outer spring is between controlling rod and servopiston, and inner spring has than the diameter of outer spring and less diameter and the short length of length, and is positioned at outer spring.
Wherein, described regulator also comprises control valve, is used for that pilot pressure is supplied to controlling rod and is positioned at wherein guide chamber and drain chamber.
Wherein, regulator also comprises gear pump being used for that pilot pressure is supplied to the 3rd piston chamber that is formed on the valve body by reduction valve from pilot conduits, acts on working pressure on the multi-level piston with increase.
Wherein, described controlling rod, described servopiston, described multi-level piston, described servo sleeve and described spring have common axis line on correlation.
Therefore, structure of the present invention is simpler, and it is little to can be controlled under the stable status operation and energy loss.
Above-mentioned and other purposes of the present invention, advantage and feature are illustrated the explanation to most preferred embodiment in conjunction with the accompanying drawings, wherein,
Fig. 1 is the flow chart that is used for the regulator of variable displacement pump according to of the present invention;
Fig. 2 is the cross sectional view according to a regulator embodiment of the present invention;
Fig. 3 is the graph of a relation of working pressure and flow;
Fig. 4 is the graph of a relation of pilot pressure and flow.
With reference to figure 1 and Fig. 2, shown is according to a regulator 10 of the present invention, a pair of variable displacement pump Pd 1And Pd 2Produced oil hydraulic pump Pd by power engine 12 drivings 1And Pd 2Flow, flow is by the method control of the angle of the wobbler 14 that changes pump.A gear pump Pg who is also driven by power engine 12 supplies with a pilot pressure fluid to regulator 10.Valve body 11 is mounted to and pump Pd 1, Pd 2Be connected with pg.The wobbler 14 of pump is by a connecting rod 18 that is fixed on the servopiston 16, with the mode of pivot be installed in servopiston 16 peripheries a bit on.Servopiston 16 has two-part, and promptly the diameter of a part is less, and the diameter of b part is bigger, and each piston portion all can slide along first valve pocket 20 that is made of valve body 11 inside and second valve pocket 22.First valve pocket 20 and pump Pd 1Fluid connection, and second valve pocket 22 is connected with fuel tank 24 by the servo guiding valve 28 that a cut-off slide valve 26 and have commutation groove 30.A servo sleeve 34 has three perforates 31,32,33 as shown in Figure 2, is used to limit a point midway, a position and the position to fuel tank 24 discharging working pressure fluids that the working pressure fluid is provided to second valve pocket by cut-off slide valve 26.One controlling rod 36 is by passing to first and second springs 38,40 of servo guiding valve 28 and be connected on the servopiston 16 acting on power difference on servopiston 16 and the controlling rod 36, changing or adjust the position in hole on the servo sleeve 34 with this.One is slidably disposed among first, second piston chamber 44,46 with controlling rod 36 contacted multi-level pistons 42, and first and second piston chamber are the multilevel shape of different-diameter, each grade diameter difference.As shown in Figure 2, controlling rod 36, servopiston 16, multi-level piston 42, servo sleeve 34, spring 38,40 all becomes coaxial relation each other with 66.
Come self-pumping Pd 1And Pd 2The working pressure fluid infeed among first and second piston chamber 44,46 by pipeline 48,50, act on pilot pressure chamber 52 and drain chamber 54 from control valve 64 through the pilot pressure fluid of pilot line 58,60; Then act on the 3rd piston chamber 56 from gear pump Pg through the pilot pressure of a reduction valve 76 and pipeline 62.The installation of gear pump Pg is in order to keep hydraulic pipe line that constant initial pressure is arranged, to prevent that when working pressure descends 10 response times of regulator lag behind.Like this, the initialization pressure of supplying with first valve pocket 20 is Pd 1Higher that pressure in the working pressure of pump and gear pump Pg.
After this, how regulator moves is to depend on the working pressure that acts on each element on the pipeline, and this is illustrated with reference to the accompanying drawings.At first, when the working pressure of coming self-pumping is lower than the spring-back force of the 3rd spring 66, servo guiding valve 28 will be moved to the left, and second valve pocket 22 is communicated with fuel tank 24.Therefore, because the working pressure that acts on first valve pocket 20 is greater than the pressure that acts on second valve pocket 22, servopiston 16 moves right, and has increased the angle of wobbler, makes the discharge amount of pump can reach its highest level.
On the other hand, when coming self-pumping Pd 1And Pd 2Working pressure summation when being higher than A point shown in Figure 3, the working pressure that acts on first and second piston chamber 44,46 has surpassed the spring-back force of spring 38,66, thereby controlling rod 36 moves right.Meanwhile, cut-off slide valve 26 also moves right because of the effect from the working pressure fluid of pipeline 68, and hole 31 and 32 is communicated with each other.Like this, just impartial in the working pressure of first valve pocket 20 and second valve pocket 22.Yet, because servopiston 16 is arranged in the hydraulic pressure compression area of second valve pocket 22 greater than the area that is arranged in first valve pocket 20, servopiston 16 just is moved to the left, reduced the angle of wobbler 14, thereby also just reduced the discharge amount of pump, and trend towards promoting outer spring 38 and be pressed on the controlling rod 36.The result is moved to the left controlling rod 36, has reduced the area of being flowed through by the fluid that forms of the relative position of the hole 31,32 of the groove 30 of servo guiding valve 28 and servo sleeve 34 and 33, thereby has reduced the working pressure of supplying with second valve pocket 22.When the working pressure of second valve pocket 22 becomes when being lower than working pressure in first valve pocket 20 once more, servopiston 16 just moves right, and controlling rod 36 is also also shifted to right-hand because of spring 38 is lax.Therefore, the to-and-fro motion of controlling rod 36, before the working pressure in chamber 20,22,44,46 reaches the synthesis pressure of balance, and before the spring-back force of spring 38,68 equates, therefore can not stop, just the horsepower of pump being controlled on the constant level.
In addition, when from Pd 1And Pd 2When the working pressure summation of pump was higher than B point shown in Figure 3, controlling rod 36 just pushed spring 38 and 40, made spring 38 and 40 be compressed simultaneously, had formed the turning point B on the oblique line as shown in Figure 3.Therefore, working pressure increases the flow decline that makes pump.The running of the running of B-C line segment and above-mentioned A-B line segment is similar.Just the slope of its slope and A-B line segment is different.
Furtherly, when working pressure became bigger than C point shown in Figure 3, the working pressure of supplying with the first cutout piston chamber 70 had overcome the spring-back force of the 4th spring 72, causes cut-off slide valve 26 to move, and directly the working pressure fluid is supplied with second valve pocket 22.Therefore, servopiston 16 move the angle just reduced wobbler 14, thereby make the discharge amount of pump drop to its minimum value, D point promptly shown in Figure 3.Cut off the control of flow, by pump delivery is reduced to minimum value, thereby make the energy loss of pump reduce to minimum value.
On the contrary, when variable displacement pump requires to have than the higher flow of C-D line segment, a pilot pressure P from outside (being represented by dotted lines) Cf, supply with the second cutout piston chamber 74.Like this, the spring-back force of the 4th spring 72 adds the pilot pressure P that imports in the second cutout piston chamber 74 Cf, just overcome the working pressure in the first cutout piston chamber 70, guaranteed that second valve pocket 22 is communicated with fuel tank 24 by the hole 31 of cut-off slide valve 26 through servo guiding valve 28, be to be higher than the pressure that C is ordered although infeed the working pressure of the first cutout piston chamber 70.So moving of servopiston 16 just increased pump Pd 1And Pd 2The flow that surpasses its minimum injection rate, and therefore removed the cut-out control of flow.
Fig. 4 is the graph of a relation between a pilot pressure and the flow.At first, with reference to Fig. 1, from the pilot pressure P of control valve 64 cDirectly infeed pilot pressure chamber 52 by pipeline 58, and pilot pressure P CdFirst quarter discharge orifice 65 infeeds drain chamber 54 by pipeline 60.Therefore, pilot pressure P cThan pilot pressure P CdHigh value is arranged.So the control of flow is by the pilot pressure P in the pilot pressure chamber 52 cWith the pressure P in the drain chamber 54 CdPressure difference Δ P finish.As shown in Figure 4, the running of its running and Fig. 3 is similar.
Get back to Fig. 3 now, it represents another horsepower control graph, i.e. A "-B "-C, and " line, it is by the pilot pressure P from gear pump Pg PsRealize.Pilot pressure P PsBe to import in the 3rd piston chamber 56, act on working pressure on the multi-level piston 42 with raising." during point, act on the push lever 36 of making a concerted effort on the multi-level piston 42, discharge amount is reduced, stably " line carries out the horsepower of control pump, and its running is similar to A-B shown in Figure 3-C line chart along A shown in Figure 3 "-B "-C when working pressure is lower than A.
Though the present invention is disclosed according to the embodiment of giving an example and is illustrated, concerning skilled person in the art, should be appreciated that various variations, modification and the interpolation made, all can not break away from the spirit and scope of the present invention.

Claims (4)

1, a kind of regulator that is used for variable displacement pump, this regulator to make it the controlling fluid flow that is produced by pump, is characterized in that described regulator comprises by means of the angle that changes wobbler: the valve body that is connected with fluid with pump; Be journaled on the wobbler and be provided with two-part servopiston, this each several part is to have different mutually diameters, is to move along first and second valve pockets that are formed in the valve body;
Can have servo guiding valve along the controlling rod that the servopiston axis moves, to be used for changing the direction of the fluid stream that comes self-pumping;
Multi-level piston contacts with controlling rod and moves along first and second piston chamber that are formed in the valve body by means of the working pressure of pump;
Servo sleeve can be contained in the controlling rod rear with restoring and be connected with servo guiding valve fluid making it to be used for limiting a point midway, and one supplies to the position of second valve pocket and a position that working pressure is discharged into fuel tank with working pressure from pump;
Cut-off slide valve that is connected with the second valve pocket fluid and servo sleeve supply to the position of second valve pocket and the position that working pressure from second chamber be discharged into servo sleeve with working pressure from pump to make it to be used for limiting;
The cutout piston that is connected with cut-off slide valve can move along the first and second cutout piston chamber, and this first Room and pump are linked up, and this second Room and pilot conduits are linked up.
It is spaced being used for a pair of spring of bias voltage controlling rod and servopiston, and outer spring is between controlling rod and servopiston, and inner spring has than the diameter of outer spring and less diameter and the short length of length, and is positioned at outer spring.
2, regulator according to claim 1 is characterized in that described regulator also comprises control valve, is used for that pilot pressure is supplied to controlling rod and is positioned at wherein guide chamber and drain chamber.
3, regulator according to claim 1 is characterized in that, regulator also comprises gear pump being used for that pilot pressure is supplied to the 3rd piston chamber that is formed on the valve body by reduction valve from pilot conduits, acts on working pressure on the multi-level piston with increase.
4, regulator according to claim 1 is characterized in that, described controlling rod, and described servopiston, described multi-level piston, described servo sleeve and described spring have common axis line on correlation.
CN94102775A 1993-02-11 1994-02-10 Regulator for a variable displacement pump Expired - Fee Related CN1033052C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR01848/93 1993-02-11
KR1019930001848A KR950013009B1 (en) 1993-02-11 1993-02-11 Wobble plate pump

Publications (2)

Publication Number Publication Date
CN1094794A CN1094794A (en) 1994-11-09
CN1033052C true CN1033052C (en) 1996-10-16

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN94102775A Expired - Fee Related CN1033052C (en) 1993-02-11 1994-02-10 Regulator for a variable displacement pump

Country Status (4)

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EP (1) EP0610940B1 (en)
KR (1) KR950013009B1 (en)
CN (1) CN1033052C (en)
DE (1) DE69400583T2 (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5567123A (en) * 1995-09-12 1996-10-22 Caterpillar Inc. Pump displacement control for a variable displacement pump
DE19735110B4 (en) * 1997-08-13 2004-09-16 Brueninghaus Hydromatik Gmbh Control device with diaphragm seal
US6623247B2 (en) * 2001-05-16 2003-09-23 Caterpillar Inc Method and apparatus for controlling a variable displacement hydraulic pump
US6848254B2 (en) 2003-06-30 2005-02-01 Caterpillar Inc. Method and apparatus for controlling a hydraulic motor
DE102010020004A1 (en) * 2010-03-05 2011-09-08 Robert Bosch Gmbh Control device and method for controlling a torque of a drive shaft of a hydrostatic machine
DE102011120082A1 (en) * 2011-12-05 2013-06-06 Man Truck & Bus Ag Adjusting device, in particular for motor vehicles
CN103511369A (en) * 2013-09-11 2014-01-15 中航力源液压股份有限公司 Multi-gear power control variable piston pump
CH714321A1 (en) * 2017-11-11 2019-05-15 Liebherr Machines Bulle Sa Adjusting device for an axial piston machine.
CN108591151B (en) * 2018-02-05 2023-11-21 江苏恒立液压科技有限公司 Hydraulic axial plunger pump power control and positive flow control mechanism

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3834836A (en) * 1973-03-01 1974-09-10 Caterpillar Tractor Co Override control for a variable displacement pump
US4381646A (en) * 1980-09-12 1983-05-03 Caterpillar Tractor Co. Torque and high pressure limiting control for variable displacement pumps
KR950007252B1 (en) * 1991-11-30 1995-07-07 삼성중공업주식회사 Control devices of oil pump of variable capacity
KR950003064B1 (en) * 1992-05-30 1995-03-30 삼성중공업 주식회사 Pump control apparatus

Also Published As

Publication number Publication date
KR950013009B1 (en) 1995-10-24
DE69400583D1 (en) 1996-10-31
KR940019991A (en) 1994-09-15
DE69400583T2 (en) 1997-02-06
CN1094794A (en) 1994-11-09
EP0610940B1 (en) 1996-09-25
EP0610940A1 (en) 1994-08-17

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