EP4051995A1 - Dispositif d'essai et procédé pour évaluer les caractéristiques de bruit d'un ensemble - Google Patents

Dispositif d'essai et procédé pour évaluer les caractéristiques de bruit d'un ensemble

Info

Publication number
EP4051995A1
EP4051995A1 EP20829312.6A EP20829312A EP4051995A1 EP 4051995 A1 EP4051995 A1 EP 4051995A1 EP 20829312 A EP20829312 A EP 20829312A EP 4051995 A1 EP4051995 A1 EP 4051995A1
Authority
EP
European Patent Office
Prior art keywords
assembly
test device
connection
determination
numerical value
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Withdrawn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
EP20829312.6A
Other languages
German (de)
English (en)
Inventor
Ralph Bründel
Alexander Störmer
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.)
ThyssenKrupp AG
ThyssenKrupp Presta AG
Original Assignee
ThyssenKrupp AG
ThyssenKrupp Presta AG
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 ThyssenKrupp AG, ThyssenKrupp Presta AG filed Critical ThyssenKrupp AG
Publication of EP4051995A1 publication Critical patent/EP4051995A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M17/00—Testing of vehicles
    • G01M17/007—Wheeled or endless-tracked vehicles
    • G01M17/06—Steering behaviour; Rolling behaviour
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H1/00—Measuring characteristics of vibrations in solids by using direct conduction to the detector
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M13/00—Testing of machine parts
    • G01M13/02—Gearings; Transmission mechanisms
    • G01M13/021—Gearings
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • G01M7/02—Vibration-testing by means of a shake table
    • G01M7/025—Measuring arrangements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • G01M7/02—Vibration-testing by means of a shake table
    • G01M7/027—Specimen mounting arrangements, e.g. table head adapters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • G01M7/08—Shock-testing

Definitions

  • the present invention relates to a test device comprising a support structure and connection structures carried by the support structure for forming a detachable mechanical connection with an assembly.
  • the present invention further relates to a method for assessing the noise behavior of an assembly, which is caused by, in particular mechanical or electrical, vibrations, which has a large number of individual elements.
  • assemblies comprise at least two individual elements.
  • assemblies comprise a multiplicity, that is to say two or more, of individual elements, that is to say components, components, building modules and / or smaller assemblies.
  • connection structures carried by the support structure are arranged on the support structure. In other words: “Carried” is to be understood as “arranged”.
  • relative movements, oscillations and vibrations can occur due to internal forces acting within the assembly, that is, between the individual elements. Such forces are also referred to as interface forces.
  • assemblies are steering systems of motor vehicles, steering columns of motor vehicles or steering gears of motor vehicles.
  • the relative movements, oscillations and vibrations can move or propagate through the structure of the assembly in the form of structure-borne noise.
  • the structure-borne sound is finally emitted from the structure of the assembly at one or more points in the form of airborne sound and thus leads to noise emission or to noise that is regularly perceived as annoying by people. But also the structure-borne noise itself - if it reaches the human user - is regularly perceived as annoying by people.
  • the object of the present invention is to create a comparatively simple way of assessing the noise behavior of an assembly, as early as possible during development Assemblies.
  • a test device comprising a support structure and, preferably two, connection structures carried by the support structure for forming a detachable, mechanical connection with an assembly.
  • each of the connection structures has a defined rigidity and is designed to form a force-fit connection with the assembly, a sensor for detecting accelerations and / or forces being arranged on each of the connection structures.
  • the test device can be a device for executing a method for assessing the noise behavior of an assembly caused by, in particular mechanical or electrical, vibrations.
  • connection structures preferably has a sensor. It is conceivable and possible to arrange several sensors on each of the connection structure in order to be able to measure several signals. It is also conceivable and possible to provide more than two connection structures, such as three, four or five, for example. Due to the defined rigidity of the connection structures and the force-fit connection between the assembly to be examined and the connection structures of the device according to the invention, it is possible to determine the interesting and relevant interface forces without the acceleration and / or force sensor or sensors on the component to place yourself. Instead, it is thereby possible to determine the interface forces of interest while the acceleration and / or force sensor or sensors is or are placed on the device according to the invention. The sensor or the sensors can thus be arranged unchanged on the test device or the test stand. Repositioning of the sensor or the sensors for each individual assembly to be tested is thus unnecessary, so that a new, time-consuming setting or calibration is also unnecessary. This shortens the time required to assess the noise behavior of interest and thus saves costs.
  • the force sensor or sensors can advantageously be placed or arranged in the force flow or within the force flow of the support structure.
  • the acceleration sensor can be designed as a shock acceleration sensor in order to be able to measure the vibrations when hard materials collide with one another. Furthermore, the acceleration sensor can be designed as a uniaxial, biaxial or particularly preferably as a triaxial acceleration sensor in order to be able to carry out the vibration measurement in all three spatial axes simultaneously.
  • a defined rigidity of the connection structures is necessary in order to realize a defined connection between the support structure and the assembly.
  • the defined rigidity is preferably a high rigidity in order to realize a rigid connection between the support structure and the assembly, that is to say in order to realize rigid connection structures.
  • Rigid connection structures are in turn required to ensure a firm, non-positive connection and to exclude interference from relative movements.
  • a high rigidity of the connection structures and a firm, non-positive connection ensure precise measurements and thus a high-quality assessment of the noise behavior of the assembly to be examined caused by mechanical or electrical vibrations.
  • the defined stiffness preferably transmits frequencies in a defined range and / or amplitudes to the respective sensor. Frequencies up to 2.5 kHz, more preferably up to 3.5 kHz, more preferably up to 5 kHz are preferably due to the rigid connection kHz, more preferably up to 10 kHz and more preferably frequencies up to 20 kHz, in order to be able to better assess the noise behavior of the assembly.
  • the rigid connection preferably transmits 90% of the movements to the sensor, more preferably 95% and more preferably 99% of the movements.
  • the test device according to the invention makes it possible to take constructive measures to improve the noise behavior at an early stage, that is to say in an early development phase. This is because the test device according to the invention can be used to find the causes of the generation of disruptive noises. In this way, disturbing noises can be reduced or avoided not only indirectly, but directly. Complex measures to compensate for disruptive noises are therefore unnecessary.
  • the test device according to the invention can be a test stand.
  • the support structure can be made in one piece or in several parts.
  • a multi-part support structure comprises two or more components. In the case of a one-piece support structure, all of the connection structures are supported by the support structure. In the case of a multi-part support structure, the connection structures are each carried by one of the components of the support structure.
  • one of the supporting structures is a clamping yoke.
  • connection structures are each jaws.
  • the assembly is a steering column or a steering gear of an electromechanical power steering for a motor vehicle.
  • a method for assessing the noise behavior, in particular mechanical or electrical, vibrations of an assembly that has a large number of individual elements.
  • the method comprises the following steps: providing a test device, in particular the test device according to the invention; Connecting the assembly to the test device via the connection structures of the device by means of a force fit; Mechanical excitation of the assembly by impressing an internal and / or external pulse; Determination of a parameter defining the noise behavior, in particular by measuring the accelerations and / or forces by means of a sensor.
  • the plurality of individual elements includes at least two individual elements.
  • An internal pulse is a pulse that is sent out from one of the components of the assembly, for example the electric motor.
  • the determination comprises the following steps: determining a transfer function describing the dynamic behavior of the assembly, in particular between a force introduction point and a force discharge point, in particular through experimental modeling, preferably by measuring the accelerations and / or forces by means of a sensor; Calculating interface forces acting between the individual elements of the assembly on the basis of the determined transfer function; Analyze the interface forces.
  • Determining a transfer function comprises the following method steps: mechanical excitation of the assembly; Detection of the accelerations and / or forces on the supporting structure caused by the mechanical excitation of the assembly.
  • the transfer function which describes the dynamic behavior of the module, can be calculated as a quotient from an input signal and an output signal. Both the input signal and the output signal are to be assumed to be known for this purpose, to be detected by sensors or to determine the like.
  • the transfer function is determined by hammer blow tests or by hammer blow excitation with an impact hammer.
  • the impact hammer comprises a force sensor on the striking side of the hammer head, that is to say on the side of the hammer head facing the assembly.
  • the force sensor records the impact or impact force when the hammer blows.
  • the hammer blow is a pulse-like mechanical stimulation of the assembly.
  • the transfer function can be calculated as the quotient of the stroke or impact force detected by the force sensor of the impact hammer and the acceleration detected by the at least one sensor of the device according to the invention.
  • the analyzing comprises the following steps: breaking down the interface forces into frequencies by means of frequency analysis; Determination of a numerical value representing the vibration behavior of the assembly by averaging or summing the frequencies. This is relatively computationally efficient and easy to implement.
  • the analysis can include the following steps: breaking down the interface forces by order analysis into order components; Determination of a numerical value representing the vibration behavior of the assembly by averaging or adding up the ordinal components. This is also relatively computationally efficient and easy to implement.
  • the analysis can comprise the following steps: breaking down the interface forces into frequencies by a filter bank; Determination of a numerical value representing the vibration behavior of the assembly by averaging or summing the frequencies. In this way, both the oscillation and the frequency-dependent distribution of the oscillation can be determined.
  • filter banks are preferably used. Filter banks are arrangements of low, band and high pass filters with which signals can be spectrally split or composed from their spectral components.
  • the analysis is particularly preferably carried out using a filter bank with 1 / n octave filters. In the 1 / n octave analysis, the oscillation to be analyzed is divided into partial signals by a digital filter bank before the level is determined.
  • the filter bank has several 1 / n-octave wide filters connected in parallel.
  • the upper limit frequency is always twice the lower limit frequency.
  • a 1/3 octave filter, also called a third octave filter, is particularly preferably used. This divides the octave bands into three parts.
  • a scalar numerical value is advantageously determined. Scalar numerical values can be handled in a computationally efficient manner.
  • the analysis can include the additional step: comparing the determined numerical value with a definable threshold value.
  • a conclusion or assessment that assesses the noise behavior of the assembly can be derived from the comparison. Description of the drawing
  • FIG. 1 shows a device known from the prior art for assessing the noise behavior of an assembly in a schematic representation
  • Figure 2 shows an embodiment of the device according to the invention in a schematic representation
  • FIG. 3 shows the device from FIG. 2 in a schematic representation with schematically indicated hammer impact tests.
  • FIG. 1 shows a test device 1 known from the prior art for assessing the noise behavior of an assembly 2 in a schematic, greatly simplified representation.
  • the device 1 designed as a test stand comprises a one-piece support structure 3 designed as a clamping yoke and two connection structures 4, each designed as clamping jaws.
  • the connection structures 4 are each carried by the support structure 3.
  • the assembly 2, which is also referred to as the test item and whose noise behavior is of interest or to be tested during operation of a motor-driven system, is connected to the test stand 1 via the connection structures 4 or is clamped into it.
  • the assembly 2 can be a subsystem of a motor vehicle, for example a steering system, a steering column or a steering gear.
  • Two acceleration sensors 5 are arranged directly on or on the assembly 2 itself. The acceleration sensors 5 serve to measure relative movements, oscillations and vibrations within the assembly 2 in order to determine the interface forces.
  • both the acceleration sensors 5 have to be arranged again on the test specimen 2 or positioned on the test specimen 2 and the clamping conditions of the test specimen 2 in the test stand 1 have to be adapted again.
  • FIG. 2 shows an embodiment of the test device 11 according to the invention in a schematic, greatly simplified representation.
  • the device 11 embodied as a test stand is used to carry out a method for assessing the noise behavior of an assembly 12 caused by mechanical or electrical vibrations, the assembly 12 comprising a multiplicity of individual elements.
  • a motor-driven system for example a motor vehicle, which comprises an assembly 12, for example a steering system, a steering column or a steering gear
  • disturbing noises caused by interface forces can arise.
  • Annoying sounds, which can be traced back to the assembly 12 are typically caused by mechanical or electrical vibrations within the assembly 12.
  • the device 11 comprises a support structure 13 designed as a clamping yoke as well as a first connection structure 14 and a second connection structure 15.
  • the two connection structures 14, 15 are each designed as clamping jaws and carried by the support structure 13, that is, arranged or attached to the support structure 13.
  • the support structure 13 is made in one piece.
  • connection structures 14, 15 serve to form a releasable, mechanical connection between the device 11, more precisely its connection structures 14, 15, and the assembly 12.
  • connection structures 14, 15 have a high degree of rigidity and are each designed to form a secure and firm non-positive connection between the device 11 and the assembly 12, specifically in a first connection area 16 and a second connection area 17.
  • the first connection area 16 is formed between the first connection structure 16 and the assembly 12.
  • the second connection area 17 is formed between the second connection structure 15 and the assembly 12.
  • a first acceleration sensor 18 is arranged or permanently installed on the first connection structure 14.
  • a second acceleration sensor 19 is arranged on the second connection structure 15 or is permanently installed thereon.
  • the acceleration sensors 18, 19 are each designed to detect triaxial accelerations of the assembly 12.
  • FIG. 3 shows the device 11 according to the invention from FIG. 2 in a schematic, greatly simplified representation with schematically indicated hammer impact tests.
  • the method according to the invention provides the method of experimental modeling. Hammer impact tests can be used for this purpose. To carry out the hammer impact tests, the assembly 12 is mechanically stimulated at various positions by a controlled impulse, that is, struck by an impact hammer.
  • a first hammer blow is performed by the impact hammer at a first hammer impact position 20, one in the hammer head of the impact hammer arranged force sensor detects the stroke or impact force of the hammer blow.
  • the hammer blow is indicated by an arrow.
  • the input signal required for calculating the transfer function is determined by recording the impact force.
  • the vibrations introduced into the assembly 12 by the hammer blow at the first hammer blow position 20 move through its structure. This means that the vibration of an element of the assembly 12 sets an element of the same assembly 12 directly adjacent to it vibrating, and so on.
  • the vibrations that are introduced and move through the assembly 12 finally reach the acceleration sensor 18 arranged on the connection structure 14 and the acceleration sensor 19 arranged on the connection structure 15. This is indicated by a dashed line in each case.
  • the accelerations caused by the vibrations are detected by the acceleration sensors 18, 19. By recording the accelerations, the output signal required for calculating the transfer function is determined.
  • a second hammer blow at a second hammer blow position 21, a third hammer blow at a third hammer blow position 22 and a fourth hammer blow at a fourth hammer blow position 23 are carried out by the pulse hammer.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)

Abstract

La présente invention concerne un dispositif d'essai (11) comprenant une structure de support (13) et des structures de liaison (14, 15), portées par la structure de support (13), destinées à établir une liaison mécanique libérable avec un ensemble (12). L'invention est caractérisée en ce que chacune des structures de liaison (14, 15) présente une rigidité définie et est conçue pour établir une liaison à force avec l'ensemble (12), un capteur (18, 19) destiné à détecter des accélérations et/ou des forces étant disposé sur chacune des structures de liaison (14, 15).
EP20829312.6A 2019-10-30 2020-10-29 Dispositif d'essai et procédé pour évaluer les caractéristiques de bruit d'un ensemble Withdrawn EP4051995A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019216784.5A DE102019216784B3 (de) 2019-10-30 2019-10-30 Prüfvorrichtung und Verfahren zur Beurteilung des Geräuschverhaltens einer Baugruppe
PCT/EP2020/000183 WO2021083539A1 (fr) 2019-10-30 2020-10-29 Dispositif d'essai et procédé pour évaluer les caractéristiques de bruit d'un ensemble

Publications (1)

Publication Number Publication Date
EP4051995A1 true EP4051995A1 (fr) 2022-09-07

Family

ID=73547491

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20829312.6A Withdrawn EP4051995A1 (fr) 2019-10-30 2020-10-29 Dispositif d'essai et procédé pour évaluer les caractéristiques de bruit d'un ensemble

Country Status (3)

Country Link
EP (1) EP4051995A1 (fr)
DE (1) DE102019216784B3 (fr)
WO (1) WO2021083539A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113983287B (zh) * 2021-10-15 2024-03-15 中国汽车技术研究中心有限公司 一种应用于高加速度试验的数据采集器缓冲放置架
CN114184343B (zh) * 2021-11-29 2023-10-17 安徽科技学院 一种齿轮特性研究用易拆装的周围自防护的冲击测试设备

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006016764B4 (de) * 2006-04-10 2009-04-30 GM Global Technology Operations, Inc., Detroit Verfahren zum Prüfen eines Kraftfahrzeuglenksystems
US7742899B2 (en) * 2008-02-12 2010-06-22 Gm Global Technology Operations, Inc. Test procedure for determining steering rack rattle
CN103149002B (zh) * 2013-02-05 2015-05-13 山东大学 一种结合面法向动态特性参数测试装置及方法
JPWO2015145914A1 (ja) * 2014-03-28 2017-04-13 日本電気株式会社 アンカーボルトの診断システム、その方法およびプログラム
CN105092153B (zh) * 2014-05-13 2018-06-26 天津航天瑞莱科技有限公司 一种高精度的大型结构件质心测量系统以及方法
DE102015122194A1 (de) * 2015-12-18 2017-06-22 Robert Bosch Automotive Steering Gmbh Verfahren zur Maskierung und/oder zur Reduzierung störender Geräusche oder deren Auffälligkeit bei dem Betrieb eines Kraftfahrzeugs
JP6225368B1 (ja) * 2016-04-21 2017-11-08 日本精工株式会社 ステアリングシステムの異音検出方法及びステアリングシステムの評価装置
DE102017212800A1 (de) * 2017-07-26 2019-01-31 Bayerische Motoren Werke Aktiengesellschaft Verfahren zum Testen eines Lenkgetriebes

Also Published As

Publication number Publication date
DE102019216784B3 (de) 2020-12-17
WO2021083539A1 (fr) 2021-05-06

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