CN102345599A - Method and system for noise control in hydraulic pumps - Google Patents
Method and system for noise control in hydraulic pumps Download PDFInfo
- Publication number
- CN102345599A CN102345599A CN2011102019441A CN201110201944A CN102345599A CN 102345599 A CN102345599 A CN 102345599A CN 2011102019441 A CN2011102019441 A CN 2011102019441A CN 201110201944 A CN201110201944 A CN 201110201944A CN 102345599 A CN102345599 A CN 102345599A
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- Prior art keywords
- pump
- flow rates
- hydraulic
- value
- hydraulic flow
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- 238000000034 method Methods 0.000 title claims abstract description 29
- 239000012530 fluid Substances 0.000 claims abstract description 38
- 238000005086 pumping Methods 0.000 claims abstract description 7
- 238000012544 monitoring process Methods 0.000 claims description 12
- 239000003921 oil Substances 0.000 description 15
- 230000001276 controlling effect Effects 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 3
- 230000003313 weakening effect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000003292 diminished effect Effects 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 239000000284 extract Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000010729 system oil Substances 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C15/00—Component parts, details or accessories of machines, pumps or pumping installations, not provided for in groups F04C2/00 - F04C14/00
- F04C15/0042—Systems for the equilibration of forces acting on the machines or pump
- F04C15/0049—Equalization of pressure pulses
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
- F04C14/08—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by varying the rotational speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/30—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
- F04C2/34—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members
- F04C2/344—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2270/00—Control; Monitoring or safety arrangements
- F04C2270/13—Noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2270/00—Control; Monitoring or safety arrangements
- F04C2270/86—Detection
Abstract
A method for attenuating hydraulic pump flow pulses is described. The method includes pumping a fluid at a first hydraulic flow rate to an operating device via the pump, the flow being in the form of discrete fluid pulses. Further, the method includes obtaining values of plurality of parameters related to the pulses produced by the pump and attenuating the pulses by modifying the first hydraulic flow rate to a second hydraulic flow rate based on the obtained values.
Description
Technical field
The application relates in general to oil hydraulic pump, particularly the noise control of pump.
Background technique
Traditional steering system produces the noise and the vibration of certain degree.Although vehicle motor just is being improved as quiet running, from other zones, like the noise of steering system, it is more and more obvious just to become.The oil hydraulic pump that is used in the power-assisted steering system is one of noise source main in the steering system.
Typically, the vehicle hydraulic steering system is used fixed displacement oil hydraulic pump or variable displacement hydraulic pump, and it provides hydraulic pressure and is used as the fluid source that flows to the steering gear.Fluid returns cistern then from pump flow toward actuator or motor, filters in order to utilize again there.For this pump power is provided by gear, belt or flexible elastic coupling flexible coupling drive electric motor or motor car engine.Each pump comprises a plurality of wheel chambers usually, causes the unsettled output stream of discontinuous fluid pulse shape.Pressure pulse or " flow fluctuation (flow ripple) " produce vibration, cause extra sound.Too much fluid pulse or flow fluctuation cause the not noise and the vibration of aspiration level, especially when pump is installed in the steering system of vehicle.Caused vibrational energy is felt by the driver, causes uncomfortable driving experience.
Along with improvement recent in the Vehicular system, when selecting hydraulic steering system, noise level has become main considering.Therefore, need weaken flow fluctuation and reduce noise and level of vibration, coming provides comfortable driving to experience for the driver of motor vehicle.
Summary of the invention
One embodiment of the present of invention have been described the method that weakens the oil hydraulic pump flow pulses.Pump is that operation equipment provides fluid with first hydraulic flow rates, and this flows is the form of discontinuous fluid pulse.In addition, this method comprises the value that obtains the one or more parameters relevant with the pulse of pump generation, and is the basis with this parameter value, changes first hydraulic flow rates into second hydraulic flow rates, makes pulse weaken.
An alternative embodiment of the invention has been described the oil hydraulic pump running system.This system comprises that being used for first hydraulic flow rates is the oil hydraulic pump that operation equipment provides fluid with the form of discrete pulses.In addition, also be useful on the monitoring module of the value that obtains the one or more parameters relevant with the pulse of pump generation.Electronic control unit (ECU) is the basis with this parameter value, changes first hydraulic flow rates into second hydraulic flow rates, makes pulse weaken.
Description of drawings
Many exemplary embodiments of the present invention are stated and explained to the accompanying drawing that describes below.In institute's drawings attached, same reference character is represented identical or functionally similar element.Accompanying drawing is illustrative in essence, does not proportionally draw.
Fig. 1 has described the example system that is used for weakening at automobile steering system the oil hydraulic pump flow pulses.
Fig. 2 is the flow chart that is used for weakening the illustrative methods of oil hydraulic pump flow pulses.
Embodiment
Make following detailed description with reference to accompanying drawing.Exemplary embodiment is to describe for purport of the present invention is described, and unrestricted its by claims institute restricted portion.
Definition:
In present specification, used following word, for the purpose of clear and convenient, defined these words at this.
Impeller (Vane):
Be contained in the structural fin-shaped object of rotation pumping.
Wheel chamber (Vane Chamber):
Volume in the pump structure is by the impeller definition of adjacency.
Pump stage (Pump Order):
The number of pumping element in the pump structure (wheel chamber).
Flow fluctuation (Flow Ripple):
Pressure pulse in the hydraulic fluid is produced by pump structure, has the character of amplitude, frequency and phase place.
The description of exemplary embodiment
The invention describes the noise control system and the method for oil hydraulic pump.Usually, motor or motor car engine (or other prime mover) for be used in power-assisted turn to similar system in oil hydraulic pump power is provided.The mobile form that is discrete pulses of fluid by pump produces causes the noise and the level of vibration that increase.Embodiments of the invention are provided for changing the method and system of the flow velocity of pump, in order to reduce noise level.
Fig. 1 representes to be used for weakening the example system 100 of automobile steering system oil hydraulic pump flow pulses.System 100 comprises a plurality of electronics and hydraulic unit, and it provides hydraulic power to the inner the steering gear 101 of automotive system.System 100 passes through the change hydraulic flow rates, and eliminates flow fluctuation constantly through the phase relationship of control flow fluctuation, and weakens the flow pulses in the automobile steering system.
Outside the pump 102, the relevant a plurality of parameters of flow pulses of the outlet of pump 102 and 112 monitorings of the monitoring module between the vehicle steering device 101 and pump 102 generations.In one embodiment, monitoring module 112 comprises transducer, and it comprises a plurality of sensors that are used for monitoring parameter.In addition, this transducer can be pressure transducer, the flow transducer that can directly carry out flow fluctuation or any other similar sensor known in the art.
Monitored parameter can comprise frequency, phase place and the amplitude of flow pulses.Pressure pulse through in the induction hydraulic fluid can directly obtain the pressure pulse frequency; Perhaps based on the constant that engine speed and pump speed are connected of engine speed and storage; The ratio of the diameter pulley of pump stage or engine crankshaft and pump diameter pulley for example can the calculating pressure pulse frequency.Calculate the relation of phase place, and regulate and flow so that the fluctuation of different phase to be provided, thereby cancel out each other.For best counteracting, has second flowing Relationship result that will offer the best who flows 180 ° of different phases with first.Can from first flow of pressurized, directly obtain the pressure pulse amplitude.Calculate the amplitude of second flow of pressurized, its amplitude with first flow of pressurized is directly proportional.
In addition, the value of monitoring module 112 transmission monitorings is to ECU110.System 100 changes first hydraulic flow rates into second hydraulic flow rates through the value based on monitoring, weakens the pulse that is produced by pump.Pulse weaken the elimination that causes flow fluctuation, provide comfortable driving to experience, noise and level of vibration minimizing.Particularly, to be flow pulses be back to the speed of pump 102 from second flow controlling unit 108 through bypass to second hydraulic flow rates, and diminished pulse dashes constantly.
Although example system 100 is parts of automobile steering system, require the system of protection in other environment, to implement, be not limited to automotive applications.Hydraulic power is used in multiple industry and application, and many such application, especially aircraft, building and manufacturing equipment, can from noise reduces, be benefited.Only, can be applicable to such application at an easy rate the system of the protection of the requirement in the scope of the invention that claims limited.
Fig. 2 is the flow chart that is used to weaken the illustrative methods 200 of oil hydraulic pump flow pulses.The system 100 that method 200 can combine to describe among Fig. 1 implements.
Oil hydraulic pump can be the pump of any other type of fixed displacement pump, variable delivery pump or generation flow pulses well known in the art.In addition, this pump can have a plurality of pumping elements or wheel chamber.
Pump provides fluid to flow with first hydraulic flow rates to operation equipment in step 202.It is continuous that this fluid flows, but the pressure that pump impeller changes in fluid is regarded as discrete pulses.Particularly, first hydraulic flow rates can be the function of this operation equipment engine speed and pump stage.
In step 204, method 200 obtains the value of the one or more parameters relevant with the pulse of pump generation.Pressure pulse through in the induction hydraulic fluid can directly obtain the pressure pulse frequency; Perhaps based on the constant that engine speed and pump speed are connected of engine speed and storage; The ratio of the diameter pulley of pump stage number or engine crankshaft and pump diameter pulley for example can the calculating pressure pulse frequency.This pressure pulse frequency is directly proportional with the rotational speed of pump, and the rotational speed of pump is again the direct function of engine speed.Thus, through utilizing engine speed signal, RPM (rpm) for example can calculate and is used to weaken the needed frequency of fluid pulse.The exemplary equation that is used to obtain the value of frequency parameter is:
f＝(RPM/60)*n*p (1)
Wherein:
RPM is the engine speed with RPM (rpm) expression,
N is pump stage (for example, 10 expression 10-wing pumps),
P is the diameter pulley of engine crankshaft and the ratio of pump diameter pulley, and
F is the frequency of the fluid pulse represented with hertz.
Calculate the relation of phase place, and regulate to flow and make fluctuation be different phase, thereby fluid stream is cancelled out each other.In order to offset fully, can be provided with second and to flow and first mobile 180 ° of different phases.Can directly obtain the pressure pulse amplitude from first flow of pressurized.Calculate the second flow of pressurized amplitude, make its amplitude be directly proportional with first flow of pressurized.
The flow pulses that method 200 is produced by pump in step 206 monitoring in addition, in step 208, produces second hydraulic flow rates and comes diminished pulse to dash through change first hydraulic flow rates based on the value that obtains.Pulse weaken the elimination that can cause flow fluctuation, provide comfortable driving to experience, reduce noise and level of vibration.
In one implemented, method 200 second hydraulic flow rates were set to and the first hydraulic flow rates different phase, weakened flow pulses and eliminated flow fluctuation constantly.In another is implemented, can the parameter value that obtain be sent to electronic control unit (ECU), its second hydraulic flow rates is set to and the first hydraulic flow rates different phase, eliminates flow fluctuation.
The change flow velocity is especially changed flow velocity through producing with the pulse of flow fluctuation different phase, causes that the active of flow fluctuation is eliminated.This is eliminated and in operation equipment, reduces noise and vibration, for the operator provides comfortable experience.
Though with the automobile hydraulic steering pump is that example is write the present invention, the application's mode of execution is applicable to similar pump environment, comprises transmission pump, AC compressor and petrolift, and the non-stationary flow kinetic energy that wherein comes from pumping installations produces the noise of dissatisfied level.In addition, oil hydraulic pump can be the pump of any other type of fixed displacement pump, variable delivery pump or generation fluid pulse well known in the art.
To those skilled in the art, be apparent that under the situation of scope that does not break away from claimed invention and expectation function, the present invention can be used in the multiple operating environment to realize the result of expectation.
Claims (20)
1. be used to weaken the method for the flow pulses that comes from oil hydraulic pump, it is characterized in that, this method comprises:
Pump fluid into operation equipment with first hydraulic flow rates through pump, wherein should flow comprises the discrete pulses of fluid;
Obtain the value of the one or more parameters relevant with the pulse of pump generation; And
Based on the value that obtains, weaken the pulse that produces by pump through first hydraulic flow rates being changed into second hydraulic flow rates, wherein second flow of pressurized is offset the pulse that is produced by first flow of pressurized.
2. the method for claim 1 is characterized in that, said parameter comprises one or more in frequency, phase place or the amplitude.
3. method as claimed in claim 2 is characterized in that, obtains the value of frequency based on the engine speed of operation equipment.
4. method as claimed in claim 2 is characterized in that, obtains the value of frequency based on pump stage.
5. method as claimed in claim 2 is characterized in that, the value of frequency is based on the diameter pulley of engine crankshaft and the ratio of pump diameter pulley.
6. the method for claim 1 is characterized in that, obtains step and comprises that further the value that transmits acquisition is to electronic control unit.
7. the method for claim 1 is characterized in that, weakens step and comprises that further second hydraulic flow rates is set to and the first hydraulic flow rates different phase.
8. the method for claim 1 is characterized in that, weakens step and is carried out by ECU.
9. the method for claim 1 is characterized in that, pump is to use the hydraulic steering pump in automobile steering system.
10. the moving system of oil hydraulic pump flow is characterized in that, comprises:
Oil hydraulic pump is configured to first hydraulic flow rates with the discrete pulses form to the operation equipment pumping fluid;
Monitoring module is configured to obtain the value of the relevant one or more parameters of the pulse that produces with pump;
Electronic control unit is configured to based on the value that obtains, and weakens the pulse that pump produces through first hydraulic flow rates being changed into second hydraulic flow rates, and wherein second flow of pressurized is offset the pulse that is produced by first flow of pressurized.
11. system as claimed in claim 10 is characterized in that, said parameter comprises one or more in frequency, phase place or the amplitude.
12. system as claimed in claim 11 is characterized in that, obtains the value of frequency based on the engine speed of operation equipment.
13. system as claimed in claim 11 is characterized in that, obtains the value of frequency based on pump stage.
14. system as claimed in claim 11 is characterized in that, obtains the value of frequency based on the ratio of the diameter pulley of engine crankshaft and pump diameter pulley.
15. system as claimed in claim 10 is characterized in that, this monitoring module comprises transducer.
16. system as claimed in claim 10 is characterized in that, this monitoring module transmits the value of acquisition to ECU.
17. system as claimed in claim 10 is characterized in that, ECU second hydraulic flow rates is set to and the first hydraulic flow rates different phase.
18. system as claimed in claim 10 is characterized in that, pump is to use the hydraulic steering pump in automobile steering system.
19. be used for reducing the method for the mobile vibration that causes of vehicle steering pump, it is characterized in that this method comprises:
Pump fluid into switching valve with first hydraulic flow rates through pump, wherein this fluid is the form of discrete pulses;
Obtain the value of the one or more parameters relevant with the pulse of pump generation;
Value based on obtaining is calculated second hydraulic flow rates; And
Reduce vibration through changing first hydraulic flow rates into second hydraulic flow rates, wherein second hydraulic flow rates and the first hydraulic flow rates different phase.
20. method as claimed in claim 19 is characterized in that, said parameter comprises one or more in frequency, pressure or the amplitude.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/841,145 US20120020807A1 (en) | 2010-07-21 | 2010-07-21 | Method and system for noise control in hydraulic pumps |
| US12/841,145 | 2010-07-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102345599A true CN102345599A (en) | 2012-02-08 |
Family
ID=45493775
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011102019441A Pending CN102345599A (en) | 2010-07-21 | 2011-07-19 | Method and system for noise control in hydraulic pumps |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US20120020807A1 (en) |
| CN (1) | CN102345599A (en) |
| RU (1) | RU2011130407A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9989059B2 (en) * | 2014-04-04 | 2018-06-05 | Ford Global Technologies, Llc | Noise-reduction mechanism for oil pump |
| US9315209B1 (en) * | 2015-01-14 | 2016-04-19 | Trw Automotive U.S. Llc | Hydraulically assisted steering system |
| GB201509228D0 (en) | 2015-05-29 | 2015-07-15 | Norgren Ltd C A | Active cancellation of a pulsating flow with a flow signal noise reference |
| GB201511982D0 (en) * | 2015-07-08 | 2015-08-19 | Norgren Ltd C A | Active cancellation of a pulsating flow with a source noise reference |
| GB201514575D0 (en) * | 2015-08-17 | 2015-09-30 | Norgren Ltd C A | DC canceller adaptive filter for attenuating noise in a feedback path of a flow controller |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4918918A (en) * | 1986-11-25 | 1990-04-24 | Daikin Industries, Ltd. | Variable displacement piston machine |
| US5492451A (en) * | 1994-10-03 | 1996-02-20 | Caterpillar Inc. | Apparatus and method for attenuation of fluid-borne noise |
| US20020065639A1 (en) * | 2000-11-29 | 2002-05-30 | Morris Hsi | Method of power steering hose assembly design and analysis |
-
2010
- 2010-07-21 US US12/841,145 patent/US20120020807A1/en not_active Abandoned
-
2011
- 2011-07-19 CN CN2011102019441A patent/CN102345599A/en active Pending
- 2011-07-21 RU RU2011130407/06A patent/RU2011130407A/en not_active Application Discontinuation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4918918A (en) * | 1986-11-25 | 1990-04-24 | Daikin Industries, Ltd. | Variable displacement piston machine |
| US5492451A (en) * | 1994-10-03 | 1996-02-20 | Caterpillar Inc. | Apparatus and method for attenuation of fluid-borne noise |
| US20020065639A1 (en) * | 2000-11-29 | 2002-05-30 | Morris Hsi | Method of power steering hose assembly design and analysis |
| US6917907B2 (en) * | 2000-11-29 | 2005-07-12 | Visteon Global Technologies, Inc. | Method of power steering hose assembly design and analysis |
Also Published As
| Publication number | Publication date |
|---|---|
| US20120020807A1 (en) | 2012-01-26 |
| RU2011130407A (en) | 2013-01-27 |
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Application publication date: 20120208 |