EP1210542A1 - Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques - Google Patents

Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques

Info

Publication number
EP1210542A1
EP1210542A1 EP00949857A EP00949857A EP1210542A1 EP 1210542 A1 EP1210542 A1 EP 1210542A1 EP 00949857 A EP00949857 A EP 00949857A EP 00949857 A EP00949857 A EP 00949857A EP 1210542 A1 EP1210542 A1 EP 1210542A1
Authority
EP
European Patent Office
Prior art keywords
volume
membrane
wall
pressure
hydraulic
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.)
Withdrawn
Application number
EP00949857A
Other languages
German (de)
English (en)
Inventor
Klaus-Jürgen KURR
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.)
Dobson Industries Corp
Original Assignee
Dobson Industries Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dobson Industries Corp filed Critical Dobson Industries Corp
Priority to EP00949857A priority Critical patent/EP1210542A1/fr
Publication of EP1210542A1 publication Critical patent/EP1210542A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/04—Devices damping pulsations or vibrations in fluids
    • F16L55/045—Devices damping pulsations or vibrations in fluids specially adapted to prevent or minimise the effects of water hammer
    • F16L55/05—Buffers therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/04—Devices damping pulsations or vibrations in fluids
    • F16L55/045—Devices damping pulsations or vibrations in fluids specially adapted to prevent or minimise the effects of water hammer
    • F16L55/05—Buffers therefor
    • F16L55/052—Pneumatic reservoirs
    • F16L55/053—Pneumatic reservoirs the gas in the reservoir being separated from the fluid in the pipe

Definitions

  • the present invention relates to a device for reducing pressure pulsations in a hydraulic line, in particular caused by a pump, according to the preamble of claim 1, and to a power steering system of a motor vehicle with the device.
  • the kinematics of the hydrostatic or other pumps mostly used in oil hydraulic circuits as well as the actuation of fittings, valves and actuators leads to pressure vibrations, which are the main cause of undesirable noises in hydraulic systems.
  • Other poles include increased strength-related stress on the pipelines, their fastenings and the connected consumers.
  • the power steering and other hydraulic consumers in motor vehicles are also supplied via hydraulic displacement units. Due to the discontinuous delivery process, these generate pressure and volume flow pulsations that propagate through the hydraulic medium in the piping system. These pulsations are particularly undesirable in power steering systems. Further suggestions can be introduced via the roadway and the wheel into the steering gear, for example in the form of pressure surges, which has an impact on driving safety.
  • a device is known from FR-834 316 for absorbing or compensating for negative pressure and strong positive pressure occurring in liquid pressure lines. For this reason, a section of the line is provided with a rubber-elastic wall, the wall of which is pressurized on its rear side by a gas.
  • DE-25 49 367 describes a device for relieving a pipeline for liquids from pressure surges.
  • the device described is only suitable for compensating for increased pressure surges and not for compensating for negative pressure.
  • a valve is opened to drain liquid from the pipeline, which is particularly the case with hydraulic lines, e.g. is unsuitable for power steering systems because it is associated with a loss of fluid.
  • this valve only opens at a certain overpressure, and the valve control is in turn very complicated with a storage tank, throttle, sealing tank, sealing liquid, etc., which is particularly unsuitable in the vehicle sector.
  • EP-A-0 633 400 and EP-0 679 832 describe adaptive, hydropneumatic pulsation dampers which are proposed for pulsating hydraulic systems with a strongly changing operating pressure and which provide a hydraulically rigid coupling between a pressure source and a consumer Hydraulic system enables. It is proposed to apply the same pressure to the damping membrane of the adaptive pulsation damper on the surface opposite to the hydraulic medium to be damped that prevails in the hydraulic medium itself. This pressure compensation takes place via a pressure compensation line which connects the hydraulic system to a gas volume which is arranged on the surface of the damping membrane opposite the hydraulic medium to be damped.
  • a throttle is arranged in this compensation line, so that pressure compensation via this throttled path only for long-term adaptation of the gas volume to the hydraulic working or operating pressure serves in the hydraulic system and therefore no pulsations are transmitted.
  • This operating pressure adaptation via a throttled line represents an additional construction element which, in addition to complicating the construction, increases the cost.
  • the stated object is achieved by means of a device according to claim 1.
  • the device according to the invention has a compensation volume through which the hydraulic system flows, and in which compensation volume a sliding wall or a Diaphragm is arranged, which wall or membrane is acted on on one side with the pulsations of the hydraulic system and on the opposite side has a back pressure to the hydraulic system, which corresponds at least almost to the mean pressure in the hydraulic system.
  • a throttle being provided in this line in order to prevent the transmission of pulsations to the opposite side of the wall or membrane.
  • Pulsation dampers and the consumer therefore form standing waves as a result of residual pulsations, since the consumer always represents a throttle point or a closed end. These residual pulsations are avoided with the direct coupling of the compensation line to the
  • Hydraulic line between pulsation damper and consumer removed. This is done by passing on the pulsation through the compensating line to a soft spring or a steam or gas cushion, which dampens the pressure peaks and thus leads to an additional damping effect. This represents a further important distinguishing feature of the device compared to the two publications mentioned, since there is no direct forwarding of pulsations up to the spring or the steam or gas cushion due to the throttle in the compensating line.
  • the spring or the vapor or gas cushion mentioned is in the area of the device according to the invention close to or at the
  • this soft spring or the gas or vapor cushion is arranged directly on that surface of the membrane or wall which is opposite to the side to which the pulsations are applied.
  • the device according to the invention can be a passive adaptive pulsation damper or an active adaptive pulsation damper which is suitable, for example, by a pump to dampen pressure pulsations generated in a hydraulic system.
  • FIG. 2 shows in section a further embodiment variant of a pulsation damper designed according to the invention
  • FIG. 3 shows in section another embodiment variant of a pulsation damper designed according to the invention.
  • FIG. 4 shows a graph in which the amplitude density spectra of the changing pressure components of a known device and of the device according to the invention for passive pulsation damping are shown.
  • a passive pulsation damper according to the invention is shown schematically and in cross section, for example, suitable for installation in a hydraulic line system of a power steering system of a motor vehicle. 1 is connected to a hydraulic line or between an inflow 3 and an outflow 5 or in the branch of a hydraulic line in such a way that the line is connected to the pulsation damper via connecting lines 3a and 5a.
  • These connecting lines 3a and 5a open into a compensation chamber 7, which is separated in the middle by a membrane 9, such as a metal membrane, an elastomer or a displaceable wall, into a hydraulic compensation volume 13.
  • the pressure equalization volume 13 is connected via openings 14 to a gas volume 17 within a storage membrane 15.
  • Gas volume 17 and storage membrane 15 form a so-called gas spring.
  • gas spring it is also possible to use a mechanical spring or other spring elements instead of this gas spring.
  • the device provided is able to dampen residual pulsations which form in the form of standing waves between the pulsation damper and the downstream consumer, in such a way that the residual pulsations can be reduced via the throttle-free compensation line 21 on the gas spring ,
  • Pulsation damper 1 consists in that a pulsation propagating in the feed line 3 reaches the compensation volume 11 via the feed section 3a.
  • the displaceable wall or membrane 9 such as, for example, a metal membrane or elastomer membrane, is deflected by the pulsation against the gas volume 13 lying above it, as a result of which the pulse is largely absorbed.
  • the hydraulic medium or the hydraulic oil leaves the compensation volume via the connecting piece 5a to the drain line 5 largely free of pulsations, so that the hydraulic medium in the compensation line 21 is also largely free of pulsations. Only residual pulsations are effective, which are of a smaller order of magnitude and which form in the form of standing waves between the pulsation damper and the consumer. However, these are connected to the gas volume via the throat-free compensation line and absorbed there.
  • FIG. 2 shows a further embodiment variant of a pulsation damper according to the invention in section, 1 differs from the damping gas spring is not arranged directly on the back of the membrane or displaceable wall.
  • the pulsation damper shown in FIG. 2 in turn has an inflow line 33 which is connected via connection lines 33a to a hydraulic compensation volume 41 in which the displaceable wall or membrane 39 is arranged.
  • the largely pulsation-free hydraulic medium leaves the compensation volume 41 via connection lines 35a and arrives in the discharge line 35.
  • the pressure compensation volume 43 opposite the hydraulic compensation volume 41 is now not formed by a gas or steam cushion, but hydraulic medium is also found in this volume.
  • This pressure compensation volume 43 is connected via an opening 44 to an oil volume 49, which communicates with the drain line 35 in the hydraulic system via a pressure compensation line 51.
  • a rubber-elastic storage membrane 45 which comprises a gas volume 47, is arranged for the actual recording of the pressure pulsations. Gas volume 47 and storage membrane 45 in turn form the so-called gas spring.
  • the principle of operation is similar to that in FIG. 1, in that the hydraulic medium reaches the hydraulic compensation volume 41 via the inflow line 33 largely perpendicularly to the membrane 39, which can be a so-called vibrating membrane. Via the outlet 35a, the hydraulic medium leaves the hydraulic compensation volume 41 and arrives in the discharge line 35.
  • the hydraulic compensation volume 41 is thus flowed through by the complete volume flow, whereby the axially clamped vibrating diaphragm 39 can compensate for volume or pressure pulsations by displacing the released volume on its opposite side and transmits this directly to the gas spring with the more easily compressible medium within the gas volume 47.
  • What is essential here is the direct coupling of the compensation volume 43 with the Gas spring via a straight and short pipe.
  • the membrane 39 is deflected by the pressure pulse and generates a volume flow pulse which flows upward through the opening 44 in the direction of the opening 46 and the oil volume 49.
  • the volume flow pulse does not propagate in the oil volume 49, but is absorbed by the soft gas spring. The absorption of the volume by the gas spring prevents the hydraulic medium from being compressed and a new pressure pulse being generated which spreads out via the compensation line 51 and the drain line 35 in the downstream system.
  • the gas storage 47 can be filled via a bore 55, i.e. biased to a certain pressure and sealed by the cover 57.
  • the pressure equalization that is necessary in order to keep the vibrating diaphragm 39 in the relieved central position at any static system pressure is realized via the equalizing line 51.
  • the parameters gas volume, gas preload pressure, vibration diaphragm thickness and installation location of the pulsation damper in a hydraulic circuit can now be used to address the respective requirements in the hydraulic system with regard to pulsation damping.
  • FIG. 3 shows a further embodiment variant of a pulsation damper according to the invention, in which case the inflow of the medium to be damped now takes place from the right side and accordingly the outflow in the plane of the drawing to the left.
  • the pulsation damper in FIG. 3 is very similar to that in FIG. 2, and analog construction parts will not be discussed again.
  • the pulsation damper in Fig. 3 has a so-called annular space 61, which by several with the middle Opening 44 communicating channels 60 is connected.
  • annular space ensures that pulsations transmitted via the membrane are not transmitted directly via the return line 51 into the drain line and thus the actual pulsation effect is only partially absorbed by the gas spring 47.
  • the cover 57 can be held on the side housing of the pulsation damper, for example by means of a clamping ring 63.
  • FIG. 4 shows the amplitude density spectra of the alternating pressure component of a known and the inventive device for passive pulsation damping, in each case before and after the pulsation damper.
  • the known pulsation damper is the one according to the teaching disclosed in EP-0 679 832, the corresponding amplitude density spectra being represented by solid lines.
  • the amplitude density spectra of the pulsation damper according to the invention are shown in the same graph with a dotted line.
  • the pulsation damper according to the invention has better damping properties than the known one.
  • the pulsation damper according to the invention thus stands out not only because of the aforementioned simpler construction from the state of the art, but also through improved damping properties.
  • a stop surface is provided in the area of the membrane in order to limit the deflection of the membrane or displaceable wall in order to prevent instability of the hydraulic system in the event of strong pulsations.
  • the configuration of the gas cushion or the gas spring can also be of various types, in that a bellows-type storage membrane 45 can be provided.
  • a bellows-type storage membrane 45 can be provided.
  • the gas cushion or the gas spring it is also possible to provide mechanical spring elements which act directly on the membrane or displaceable wall, in order to have a damping effect on the latter when it is deflected as a result of pulsations.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Pipe Accessories (AREA)
  • Supply Devices, Intensifiers, Converters, And Telemotors (AREA)
  • Reciprocating Pumps (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Diaphragms And Bellows (AREA)
  • Vibration Prevention Devices (AREA)

Abstract

L'invention concerne un dispositif pour réduire des pulsations de pression provoquées notamment par une pompe dans un système hydraulique. Ce dispositif comprend un volume de compensation (41) qui présente une paroi ou une membrane (39) mobile, placée dans ledit volume et obturant ce dernier. Cette paroi ou membrane est soumise aux pulsations d'un côté, et à une contre-pression, du côté opposé, correspondant au moins approximativement à la pression moyenne régnant dans le système hydraulique. Le volume de compensation de pression (43) placé sur le côté opposé de la paroi ou de la membrane (39) est raccordé au système hydraulique par l'intermédiaire d'une conduite de compensation (51) qui débouche dans le système hydraulique, en aval du volume de compensation (41), dans le sens de propagation des pulsations.
EP00949857A 1999-09-06 2000-08-22 Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques Withdrawn EP1210542A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP00949857A EP1210542A1 (fr) 1999-09-06 2000-08-22 Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP99117582 1999-09-06
EP99117582A EP0971164A3 (fr) 1999-09-06 1999-09-06 Dispositif de réduction de pulsations de pression dans des conduits hydrauliques
PCT/IB2000/001142 WO2001018443A1 (fr) 1999-09-06 2000-08-22 Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques
EP00949857A EP1210542A1 (fr) 1999-09-06 2000-08-22 Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques

Publications (1)

Publication Number Publication Date
EP1210542A1 true EP1210542A1 (fr) 2002-06-05

Family

ID=8238934

Family Applications (2)

Application Number Title Priority Date Filing Date
EP99117582A Withdrawn EP0971164A3 (fr) 1999-09-06 1999-09-06 Dispositif de réduction de pulsations de pression dans des conduits hydrauliques
EP00949857A Withdrawn EP1210542A1 (fr) 1999-09-06 2000-08-22 Dispositif pour reduire des pulsations de pression dans des conduites hydrauliques

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP99117582A Withdrawn EP0971164A3 (fr) 1999-09-06 1999-09-06 Dispositif de réduction de pulsations de pression dans des conduits hydrauliques

Country Status (10)

Country Link
EP (2) EP0971164A3 (fr)
JP (1) JP2003534500A (fr)
KR (1) KR20020056886A (fr)
CN (1) CN1399711A (fr)
AU (1) AU6311200A (fr)
BR (1) BR0013747A (fr)
CA (1) CA2383869A1 (fr)
MX (1) MXPA02002433A (fr)
WO (1) WO2001018443A1 (fr)
ZA (1) ZA200201020B (fr)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1256755A1 (fr) * 2001-05-11 2002-11-13 Dobson Industries Corp. Dispositif de réduction des oscillations de pression dans les conduits hydrauliques
DE112005002804B4 (de) * 2004-11-19 2014-07-31 Richard Bergner Verbindungstechnik Gmbh & Co. Kg Hydraulikaggregat sowie Verfahren zur Bereitstellung einer unter Druck stehenden Hydraulikflüssigkeit
DE102009006980A1 (de) * 2008-02-08 2009-08-13 Continental Teves Ag & Co. Ohg Hydraulikaggregat mit verbesserter Pulsationsdämpfung
CH702905A1 (de) * 2010-03-26 2011-09-30 Olaer Schweiz Ag Druckausgleichsvorrichtung für flüssigkeitsdurchströmte Systeme.
DE102011117620A1 (de) * 2011-11-04 2013-05-08 Eads Deutschland Gmbh Vorrichtung zur Reduzierung einer Druckschwankung in einer fluidgefüllten Leitung
JP5810446B2 (ja) * 2012-02-24 2015-11-11 株式会社アドヴィックス ダイヤフラム装置
JP5595457B2 (ja) * 2012-09-05 2014-09-24 東海ゴム工業株式会社 コネクタ
PT2722575T (pt) * 2012-10-16 2017-12-11 Water Powered Tech Limited Acumulador de mola de gás
EP3126200A1 (fr) * 2014-04-03 2017-02-08 Robert Bosch GmbH Dispositif d'amortissement et système de freinage de véhicule à anti-patinage
JP6435684B2 (ja) * 2014-07-23 2018-12-12 株式会社Ｓｏｋｅｎ 配管
CN105650063B (zh) * 2016-01-28 2019-01-18 中国重型机械研究院股份公司 挤压机液压系统压力波动降低方法
JP6575487B2 (ja) * 2016-11-24 2019-09-18 株式会社アドヴィックス 脈動低減装置及び液圧制御装置
CN107559467B (zh) * 2017-08-01 2019-02-01 哈尔滨工程大学 一种三螺杆泵流体脉动蓄能安全阀
CN109899274A (zh) * 2017-12-12 2019-06-18 攀谷科技(北京)有限公司 流体脉冲整流器
CN110425102B (zh) * 2019-08-06 2020-12-22 大连依利特分析仪器有限公司 一种可调式输液泵脉动阻尼器
CN110886726B (zh) * 2019-11-08 2021-07-23 陕西航天动力高科技股份有限公司 一种隔膜泵出口双缓冲器
CN115151816A (zh) 2019-11-27 2022-10-04 沃特世科技公司 梯度比例阀
JP2021173327A (ja) * 2020-04-24 2021-11-01 宣行 杉村 脈動減衰装置
CN111706739A (zh) * 2020-06-24 2020-09-25 华中科技大学 一种分频组合压力脉动衰减装置及方法
CN114151643B (zh) * 2021-12-27 2024-04-09 青海盐湖海纳化工有限公司 一种用于液化气体输送的液锤消除器及液锤消除方法

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GB254041A (en) 1925-04-09 1926-07-01 Gross Sherwood & Heald Ltd Improvements in the manufacture of nitro-cellulose varnishes
FR834316A (fr) 1937-07-16 1938-11-17 Socea Dispositif amortisseur d'ondes dans les conduites sous pression
US3933172A (en) 1975-02-24 1976-01-20 Grove Valve And Regulator Company Pipeline surge reliever with sanitary barrier
GB2054041A (en) 1979-02-08 1981-02-11 Johal K S Surge Suppression Device
DE3339876A1 (de) 1983-11-04 1985-05-15 Volkswagenwerk Ag, 3180 Wolfsburg Dehnschlauch zur reduzierung von druckpulsationen
DE4318553C2 (de) 1993-06-04 1995-05-18 Daimler Benz Ag Adaptiver hydropneumatischer Pulsationsdämpfer
US5530774A (en) 1994-03-25 1996-06-25 Eastman Kodak Company Generation of depth image through interpolation and extrapolation of intermediate images derived from stereo image pair using disparity vector fields
EP0679832B1 (fr) 1994-04-26 1998-09-23 Lüthin, Heinz Dispositif de réduction de pulsations de pression dans conduits hydrauliques

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Also Published As

Publication number Publication date
CA2383869A1 (fr) 2001-03-15
BR0013747A (pt) 2002-05-21
EP0971164A3 (fr) 2000-04-05
ZA200201020B (en) 2003-11-26
CN1399711A (zh) 2003-02-26
JP2003534500A (ja) 2003-11-18
EP0971164A2 (fr) 2000-01-12
KR20020056886A (ko) 2002-07-10
MXPA02002433A (es) 2004-07-16
WO2001018443A1 (fr) 2001-03-15
AU6311200A (en) 2001-04-10

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