1、February 2013DEUTSCHE NORM Normenausschuss Akustik, Lrmminderung und Schwingungstechnik (NALS) im DIN und VDIDIN-SprachendienstEnglish price group 14No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berl
2、in, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 13.160!%37“2021620www.din.deDDIN 45679Mechanical vibration Measurement and evaluation of coupling forces for assessment ofvibration exposure of the hand-arm system,English translation of DIN 45679:2013-02Mechanische Sc
3、hwingungen Messung und Bewertung der Ankopplungskrfte zur Beurteilung derSchwingungsbelastung des Hand-Arm-Systems,Englische bersetzung von DIN 45679:2013-02Vibrations mcaniques Mesurage et valuation des forces de couplage pour le jugement de lexposition auxvibrations transmises au systme main-bras,
4、Traduction anglaise de DIN 45679:2013-02SupersedesDIN 45679:2005-09www.beuth.deDocument comprises 33 pages08.13 DIN 45679:2013-02 2 A comma is used as the decimal marker. Contents Page Foreword . 3 Introduction 4 1 Scope . 5 2 Symbols and indices 5 3 Parameters at hand-grip interface 6 3.1 Contact p
5、ressure 6 3.2 Push force . 7 3.3 Guiding force . 8 3.4 Lifting force . 8 3.5 Gripping force . 9 3.6 Feed force 11 3.7 Contact forces . 11 3.8 Coupling force . 12 3.9 Torsion and friction 13 4 Parameters for the coupling-dependent evaluation of the vibration exposure . 13 4.1 Coupling factor ccp13 4.
6、2 Coupling-dependent frequency-weighted acceleration ahwc13 4.3 Coupling force-dependent vibration total value ahvc. 13 4.4 Coupling force-dependent daily vibration exposure value A(8)c. 14 5 Measuring procedure and evaluation of measurement results . 14 5.1 General . 14 5.2 Measuring the gripping f
7、orce 14 5.3 Measuring the push force 15 5.4 Measuring the pressure distribution on the contact surface of the hand 16 5.5 Processing the measurement results: Time history . 16 5.6 Processing the measurement results: Averaging the values 16 5.7 Evaluation of the measurement results . 17 6 Calculation
8、 of the coupling force-dependent values 17 6.1 Coupling force-dependent frequent-weighted acceleration 17 6.2 Coupling force-dependent vibration total value and daily vibration exposure value . 19 Annex A (normative) Requirements for measuring equipment. 20 Annex B (informative) Biodynamic effects o
9、f machine contact forces . 23 Annex C (informative) Calculation of the gripping force and push force from a pressure measurement . 25 Annex D (informative) Measurement report. 27 Annex E (informative) Calibration and methods for comparison of different force measuring instruments . 29 Annex F (infor
10、mative) Examples of typical coupling forces and coupling factors . 31 Bibliography . 32 DIN 45679:2013-02 3 Foreword The standard has been prepared by Working Committee NA 001-03-07-02 UA (NALS/VDI C 7.2) Hand-Arm-Schwingungen in the Normenausschuss Akustik, Lrmminderung und Schwingungstechnik im DI
11、N und VDI (NALS) (Acoustics, Noise Control and Vibration Engineering Standards Committee in DIN and VDI). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be held responsible for identifying any or all such patent rig
12、hts. Amendments The standard differs from DIN 45679:2005-09 as follows: a) coupling forces are now included in general; b) the forces and measuring methods described in ISO 15230 have been integrated; c) annexes containing additional information are now included. Previous editions DIN V 45679: 1998-
13、01, 1998-10 DIN 45679: 2005-09 DIN 45679:2013-02 4 Introduction Measurements shall be carried out directly at the application point into the hand-arm system for an exact determination of the vibration exposure of the hand-arm system by a hand-held or hand-guided machine or a control element. As this
14、 is not feasible for technical reasons, the vibrations are measured on the handle of the machine or the control element. In the case of measurements on the handle of the machine, the coupling of the hand on the machine or the control element has a considerable effect on the measurement result and th
15、e exposure of the hand-arm system. Thus a stronger coupling causes a reduction in the measured acceleration values at the handle, as more energy is transferred to the hand-arm system. In addition, further factors (e.g. thermal and ergonomic factors) can affect the vibration exposure of the operator.
16、 It is technically difficult during measurements to separate the various forces which act on the hand-arm system or are transferred through it and thus to differentiate them by using different terms, e.g. gripping force, steering force, guiding force, feed force, pull force, push force. In particula
17、r, the push force is ambiguous if it does not act in the same direction as the feed. To take account of the above influences, the measurement of the coupling forces is carried out during vibration measurements. The coupling force-dependent frequency-evaluated acceleration then replaces the frequency
18、-weighted acceleration ahwin the existing standards. In future, workplace measurements for measuring and evaluating mechanical vibration acting on persons are to consider the effect of the coupling forces of the hand-arm system on the handle of the machine or control element. The coupling forces con
19、siderably influence both the measured vibration values of the machines as well as the exposure of the hand-arm system. In the majority of hand-held and hand-guided devices, the coupling force is between 80 N and 200 N. For these devices the coupling factor is between 0,85 and 1,1 (i.e. correction by
20、 a value between 15 % and +10 %) and hence within the range of measurement uncertainty. An evaluation of the coupling forces is therefore only necessary in special cases. In the case of such hand-held and hand-guided machines and for measurements at steering wheels where only low coupling forces ( 5
21、 Hz). In an alternative approach, the magnitude of the biodynamic force in each direction can be estimated using the dynamic mass or dynamic impedance of the system and the machine acceleration in the corresponding direction. As the first degree of approximation, the biodynamic force can be estimate
22、d using the following equations: ( )JiJiJiMF a )()(BD(B.1) ( ) ( )iJiJiJiZF a )(BD(B.2) where a is the root-mean-square (r.m.s.) value of the machine acceleration; J is the hand coordinate; M is the dynamic mass; Z is the dynamic impedance; iis the angular frequency of the ith spectral component. Th
23、e r.m.s. value of the biodynamic force in each direction can thus be estimated using its corresponding component at each frequency using the following equation: ( )=iJiJFF 2BDBD(B.3) DIN 45679:2013-02 24 B.3 Fundamental characteristics of the biodynamic force Because the dynamic mass generally decre
24、ases with an increase in frequency, the biodynamic force is generally much higher when working with a machine that generates dominant low-frequency vibration ( 40 Hz) than those that produce high frequencies ( 100 Hz). The low-frequency biodynamic force may be comparable with the applied forces on s
25、ome machines. Because the dynamic mass in the z direction (along the forearm direction) is generally the highest among those in the three orthogonal axes, the biodynamic force in this direction is also generally the highest one. The biodynamic force usually reaches its maximum value at the dominant
26、frequency of the machine vibration. The fundamental resonance frequency of the hand-arm system is usually in the range of 10 Hz to 63 Hz. If the dominant frequency of a machine is in this range, the biodynamic force could become especially significant. At frequencies lower than 100 Hz, the biodynami
27、c force in a grip action or a combined grip and push action is primarily distributed across the palm of the hand. This is especially true for biodynamic forces in the z direction. At higher frequencies, however, the biodynamic force components distributed at these two parts of the hand are comparabl
28、e. DIN 45679:2013-02 25 Annex C (informative) Calculation of the gripping force and push force from a pressure measurement C.1 General The push, gripping and coupling forces can be calculated from the mapping of local pressure and the geometry of the grip zone. It is essential to know, for each tran
29、sducer, the relative angle between its surface and the main gripping force axis. The state of the art allows mapping pressure without interpolation. When the number of transducers is insufficient to cover the whole surface of the hand in contact with the grip zone, it is necessary to make an interpo
30、lation between transducers. C.2 Push force The push force Fpuis calculated as follows (see Figure C.1): =iiiiiiiiiSpFFF coscosc,pu,pu(C.1) NOTE When the feed force is not in the direction of the push force, it can be useful to calculate the resultant forces in this direction as well. In this case, t
31、he following definition of the real push force can be used: )sincos(RP iiiiijiSpF +=(C.2) where iand jare the coordinate axes of the vector. RPFis a vector quantity which can be measured in the plane orthogonal to the handle axis and provides information on the posture of the operator during the tes
32、t. Its direction can be time-dependent. a) Elliptic handle b) Round handle Figure C.1 Angle between local normal force Fc,iand direction of the push force FpuDIN 45679:2013-02 26 C.3 Gripping force The gripping force is calculated as follows. At first, a grip action Fgr projected along all possible
33、directions xaround the handle is calculated (see Figure C.2): =ixxiFpF pu,gr21 (C.3) where xis the projected direction; ,ixpis the force applied on the ith transducer, projected along x; xFpu,is the push force projected along x. Figure C.2 Grip orientation with information for calculations Based on
34、this, then a) the push-oriented gripping force Fgr,puis defined as gripping force Fgr calculated along direction pu,x of the push vector RPF, which can vary during the test, depending on operator pressure (see Clause C.2): =ixxiFpFpu,pu,pu,pugr,21(C.4) b) the maximum gripping force is defined as: gr
35、20grmax FF= (C.5) C.4 Coupling force The coupling force Fcpis calculated as follows (see Figure C.1): ( ) ( )+=+=+=iiiiiSpFFFFF coscos21pupuc,21grpucp(C.6) DIN 45679:2013-02 27 Annex D (informative) Measurement report The measurement report should contain the following information: a) General inform
36、ation: Manufacturer and user; Purpose of the measurement; Measurement date; Data on the person operating the vibrating machine; Person responsible for the measurement and implementation. b) Ambient conditions at the workplace: Site of the measurement; Temperatures (e.g. ambient, at the vibrating sur
37、face, at the measuring transducer); Air humidity. c) Description of the task: Detailed description of the work process; Movement directions of the handle, the vibration surface and the hand; Gripping conditions; Posture of the operator (e.g. photos, video). d) Anthropometry: Dominant hand of the ope
38、rator; Dimensions of the hand (length, width, length of the middle finger). e) Information on the machine or control element: Manufacturer, type, type number, serial number, operating conditions, weight, function (for control elements): Machine and tool; Description of the machine; Type and model nu
39、mber; Age and condition of the machine; DIN 45679:2013-02 28 Weight of the machine or control element; Type of handle; Power of the machine; Excitation frequency of the machine; Model and type of the tool used; Workpiece. f) Measuring equipment: Detailed description of the measuring chain; Calibrati
40、on report; Date of the last calibration; Result of the functional test. g) Measuring conditions: Description of the measuring method; Direction of the measurement; Measurement duration; Method of transducer mounting; Operating conditions. h) Measurement results: Measured forces and pressures; Coupli
41、ng force; Time history of the measured forces and pressures; Measurement uncertainty. i) Further processing the measurement results: Evaluation with reference to this standard: Frequency-weighted acceleration ahw, coupling force Fcp, coupling factor ccp, coupling force-dependent frequency-weighted a
42、cceleration ahwc, if necessary coupling force-dependent vibration total value ahvcand coupling force-dependent daily vibration exposure value A(8)c. DIN 45679:2013-02 29 Annex E (informative) Calibration and methods for comparison of different force measuring instruments E.1 Calibration of force tra
43、nsducers Force measuring devices can be calibrated effectively at a static load of 100 N. It is also recommended that a load that is up to 90 % of the transducer maximum be used to establish the transducer linearity. For gripping force measurements, an additional calibration at 50 N should be perfor
44、med. The measurement point is the centre of the transducer. In many cases, it is necessary to take into account the temperature deviation between the calibration and the measurement. E.2 Calibration of pressure transducers Pressure transducers may be calibrated using a press consisting of a rubber m
45、embrane and a flat solid surface, between which the transducers are laid. Compressed air is fed in so as to exert a homogeneous pressure distribution on the transducers via the rubber membrane. The press should be capable of calibrating transducers up to 1 N/mm2. The air pressure is measured using a
46、 manometer with an accuracy of 0,01 N/mm2. Different pressure values within the measurement range are applied in order to draw a calibration curve for each transducer. E.3 Reference method for comparing different force-measuring instruments Figure E.1 gives an example of a handle with a force transd
47、ucer. Various devices (strain gauges, pressure transducers, etc.) are fixed on one side of the handle. A wrapping band is placed over the device and loaded on both sides with a load of 50 N. The width of the band should correspond to the width of the transducers to be calibrated. Key 1 transducer Fi
48、gure E.1 Example of a reference handle used to compare different force measuring instruments DIN 45679:2013-02 30 E.4 Alternative method for comparing different force-measuring instruments Use of force-measuring instruments can result in a non-linear transfer factor for the applied force. In case of doubt, it is recommended that the measuring cells be checked at three measurement points,
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