Nominal location of C-axis centerline. Z axis. Actual centerline. X axis. x CB. Y axis C C. B axis. C axis Z Y

HTML
DOWNLOAD

Μέγεθος: px

Εμφάνιση ξεκινά από τη σελίδα:

Download "Nominal location of C-axis centerline. Z axis. Actual centerline. X axis. x CB. Y axis C C. B axis. C axis Z Y"

Αδελφά Ιωαννίδης
8 χρόνια πριν
Προβολές:

1 5 Λ (D5) ΛΛ ΛΛΛ y y ΛΛ yy Identi cation of Motion Error Sources on Five-axis Machine Tools by all-bar Measurements (1st Report) lassi cation of Motion Error omponents and Development of the Modi ed all ar Device (D5) Soichi IARAKI, Yoshiaki KAKINO, Takayuki AKAI, Naoshi TAKAYAMA, Iwao YAMAJI and Keiji OGAWA The inclusion of the application of the double ball bar (D) measurement to the accuracy calibration of ve-axis machine tools into the revision of ISO standards is currently under the discussion. This paper presents the modi ed D measurement device, referred to as D5 in our study, where master balls are supported from the 45 ffi direction to the spindle axis. It can perform all the circular tests on XY, YZ, and ZX planes without changing the setup. This paper rst presents the classi cation of motion error components of a ve-aixs machine tool into location and component errors. Experimental application examples of the D5 to the calibration of location and component errors assciated with rotary axes on a ve-axis machine tool are then presented. Key words: ve-axis machine tool, measurement, ball bar, component error, location error ISO 1) ISO ο3 2) Double all ar (D) 3, 4) 5, 6, 7, 8) ISO T39/S2 ISO ) 5 ΛΛ ΛΛΛ y yy 2 1) 11) 12) 13) 14) R-test 5 15) ISO ) NAS979 16) 18) 5 5 D5 D ) 2) 3)

2 Z axis Nominal location of -axis centerline Actual centerline x ( ) cos( ) y ( ) sin( ) Y axis X axis x axis axis (a) Shift of -axis center to X direction, ffix Y. Fig. 2 (b) Run-out of -axis, ffix Y () and ffiy Y () (ffi, ffi: constant) Example of a location error anda component error Fig. 1 on guration of the experimental ve-axis machining center 21) 4) 3) 1)2) ) 2(a) ffix 1 2(b) ffix, ffiy Z ffiz Y ffiz Y () 22) ff (), fi () 5 2 ISO ) component errors location errors 2 Table 1 Location errors for the machine con guration shown in Fig. 1. Symbol 2) Symbol 19) Description Location errors associatedwith rotary axes ff Y E A Squareness error of - to Z-axis fi Y E Orientation of -axis aroundy-axis fl Y E Squareness error of - to X-axis ff E A E A Squareness error of - to -axis ffix Y E X Linear shift of -axis in x direction ffiy Y E Y Linear shift of -axis in y direction ffiz Y E Z Linear shift of -axis in z direction ffix E Y E Y Linear shift of -axis from -axis in X Location errors associatedwith linear axes fl YX E Y Squareness error of Y- to X-axis ff ZY E AZ Squareness error of Z- to Y-axis fi ZX E Z Squareness error of Z- to X-axis Z Y X Fig. 3 on guration of the conventional D device 3) Fig. 4 on guration of the modi ed D device, D5 3. (D5) 3 3) 2 3 XY 36 ffi YZ, ZX 18 ffi YZ, ZX 36 ffi 4) 4 (D5) 45 ffi XY YZ ZX D5 5 component errors

3 Table 2 omponent errors andtheir possible causes (those associatedwith -axis) for the machine con guration in Fig. 1 Symbol Symbol 17) Description omponent errors of rotary axis Y() E A Orientation changes of -axis with rotation Y() E Angular error of -axis rotation Y() E Orientation changes of -axis with rotation (, ) E A-E A Orientation changes of -axis with, rotation (, ) E -E Orientation changes of -axis with, rotation (, ) E -E Angular error of -axis rotation x Y() E X Location changes of -axis center with rotation y Y() E Y Location changes of -axis center with rotation z Y() E Z Location changes of -axis center with rotation x (, ) E X-E X Location changes of -axis center with, rotation y (, ) E Y-E Y Location changes of -axis center with, rotation z (, ) E Z-E Z Location changes of -axis center with, rotation omponent errors of linear axis YX(Y) E Y Yaw changes of Y-axis with Y motion YX(Y) E AY Pitch changes of Y-axis with Y motion YX(Y) E Y Roll changes of Y-axis with Y motion x YX(Y) E XY Straightness of Y-axis y YX(Y) E YY Linear positioning error of Y-axis z YX(Y) E ZY Straightness of Y-axis Possible major error causes Errors in positioning mechanism Errors in rotary encoder Pitch error in transmission mechanism (e.g. worm gear) Inaccurate pitch error compensation Errors associated with bearings Run-out Angular motion of rotation centerline Profile error caused by geometric error of rings Profile error caused by variation in roller size Gravity influence Deformation of rotating unit Angular positioning error caused by gravity influence 4. D5 (D5) 5 NMVDG 21) 1 DD Y Z 2 X 1 D5 D mm 4.1 XY, YZ, ZX XY, YZ, ZX mm/min. Z-Y Z-X ff ZY =1:2μm=168mm fi ZX = 3:μm=168mm 3) Location Errors 36 6(a)ο(d) 6(a-1)( -X (-Z) ) 36 ffi X 6(b-1)( -Y (-Z)) Y 6(c-1)(d-1)( -X (+Z), -Y (+Z)) +Z Z d z =mm 72 ffi /min X (-Z), -Y (-Z), -X (+Z), -Y (+Z) r x1, r y1, r x2, r y2 Z Y X fi Z, ff Z 2 W Fig (a)xyplane W (b) YZ plane. (c) XZ plane. Error pro les of circular test on XY, YZ, andxz planes. fi Z = (r x2 r x1) =d z = 4:2μm=mm (1) ff Z = (r y2 r y1) =d z =+5:5μm=mm (2) XY X, Y ffi x;y, ffi y;y ffi x;y = r x1 fi Z Z 1; ffi y;y = r y1 + ff Z Z 1 (3) Z 1 -X (-Z) Z Z = omponent Errors -X -Y 36 ffi X, Y 22) ffix A() ffiy A() 7 -Z 22) (ffiz A())

4 Table 3 ircularity error andmean radial error of Measurements -X (low), -Y (High), -X (Low), and-y(high). -X (-Z) -Y (-Z) -X (+Z) -Y (+Z) ircularity error μm Mean radial rx1 = ry1 = rx2 = ry2 = error μm Table 4 ircularity error andmean radial error of Measurements -X (-Y), -Z (-Y), -X (+Y), and-z (+Y). -X (-Y) -Z (-Y) -X (+Y) -Z (+Y) ircularity error μm Mean radial rx1 = rz1 = rx2 = rz2 = error μm (c-2)(d-2) -Λ(+Z) 6(a-2)(b-2) -Λ(-Z) 22) ff Z(), fi Z() ISO ISO ) ff Z, fi Z 8(f-1) Annex,K2 XY 8(f-2) W ( x; y)=( :4; +:7) μm X Y 5, 8) fi Y = x=r = :3μm=mm (4) ff Y = y=r = :5μm=mm (5) R =135mm -X, -Y (1)(2) mm μm X Y Z -XY 8 XY Z -XY 6 XY location errors 4 8(f-2) 7(e-2) -Z 7 -XY 8 XY ISO ) 8(f-1) 4.3 9(g)ο(j) X Z 4 4 -X (-Y), -Z (-Y), -X (+Y), -Z (+Y) r x1, r z1, r x2, r z2 X Z ff Y, fl Y fl Y = (r x2 r x1) =d y =+2:7μm=271mm (6) ff Y = (r z2 r z1) =d y =+1:4μm=271mm (7) 3μm -Y +Y (g)(i) 145 ffi, (h)(j) 19 ffi 36 ffi (a)ο(f) 1 -Y 2μm 4.4 NAS979 16) 5 ISO/DIS :212 17) 14) ISO/DIS :212 9) 11(l- 1) 11(l-2) +X 1μm 5. (1) 5 (2) 45 ffi D (D5) 3 36 ffi (3) 5 D5 (4) 4 D D5 3 1) 78, 7 (212) ) ISO :1998, Test conditions for machining centres Part 1: Geometric tests for machines with horizontal spindle and with accessory heads (horizontal Z-axis). 3) D N,199.

5 4) ISO 23-4: Test code for machine tools Part 4: ircular tests for numerically controlledmachine tools, (25). 5) Kakino, Y., Ihara, T., Sato, H., Otsubo, H., A Study on the motion accuracy of N machine tools (7th report) Measurement of motion accuracy of 5-axis machine by D tests, Journal of Japan Society for Precision Engineering, 6, 5(1994), 718 (in Japanese). 6) 5 ( ), 63, 65 (1997) ) Abbaszaheh-Mir, Y., Mayer, J. R. R., lotier, G., Fortin,., Theory andsimulation for the identi cation of the link geometric errors for a ve-axis machine tool using a telescoping magnetic ball-bar, Int'l J. of Production Research, 4, 18 (22), ) 5 2 3, 69, 2 (23) ) ISO/DIS :212, Test conditions for machining centres Part 6: Accuracy of speeds and interpolations. 1) K. M. Muditha Dassanayake, Masaomi Tsutsumi, Akinori Saito: A strategy for identifying static deviations in universal spindle head type multi-axis machining centers, International Journal of Machine Tools andmanufacture, 46, 1 (25), ) K. M. Muditha Dassanayake:,75, 7 (29), ) 73, 5 (27), ) 5 72, 1 (26) ) ( 1 ) 5 M 71, 12 (25) ) S. Ibaraki, W. Knapp, Indirect Measurement of Volumetric Accuracy for Three-Axis andfive-axis Machine Tools : A Review, Int l J. of Automation Technology, 6, 2 (212) ) NAS 979: Uniform cutting test metal cutting equipments, ) ISO/DIS 171-7:212, Test conditions for machining centres Part 7: Accuracy of a nishedtest piece. 18). Hong, S. Ibaraki, anda. Matsubara, InΛuence of positiondependent geometric errors of rotary axes on a machining test of cone frustum by ve-axis machine tools, Precision Engineering, 35-1, pp. 1-11, ) ISO 23-1:212, Test code for machine tools Part 1: Geometric accuracy of machines operating under no-load or quasi-static conditions. 2) (1997). 21) NMV DG (28). 22) ISO 23-7:26, Test code for machine tools Part 7: Geometric accuracy of axes of rotation. (a-1) Meas. -X (-Z). (b-1) Meas. -Y (-Z). (c-1) Meas. -X (+Z). 2 2 W (a-2) Error pro les (-X (-Z)) W (b-2) Error pro les (-Y (-Z)) W (c-2) Error pro les (-X (+Z)) W 1 2 (d-1) Meas. -Y (+Z). Fig (d-2) Error pro les (-Y (+Z)). Measurement -X and-y W 1 2 1μm/div 2 (e-1) Meas. -Z 2 2 Fig. 7 (e-2) Error pro les (-Z). Measurement -Z.

6 2 1 W X, Y 1 2 (f-1) Meas. -XY (f-2) Error pro les (-XY). 2 1 Fig. 8 Measurement -XY. Z Y X (g-1) Meas. -X (-Y) W (g-2) Error pro les (-X (-Y)) (k-1) Meas. -Y 2 2 Fig W (k-2) Error pro les (-Y). Measurement -Y. 1 2 W 2 (h-1) Meas. -Z (-Y). 2 2 (h-2) Error pro les (-Z (-Y)) (i-1) Meas. -X (+Y) W (i-2) Error pro les (-X (+Y)). Z mm Spindle-side ball X 45 Machine table Rotation center of -axis Table-side ball mm (l-1) Measurement 2 schematics in the workpiece cordinates. Fig W (l-2) Error pro les. Measurement correnspoinding to cone frustum machining test. 1 2 W (j-1) Meas. -Z (+Y). Fig (j-2) Error pro les (-Z (+Y)). Measurement -X and-z.

Σχετικά έγγραφα

Homework 8 Model Solution Section

MATH 004 Homework Solution Homework 8 Model Solution Section 14.5 14.6. 14.5. Use the Chain Rule to find dz where z cosx + 4y), x 5t 4, y 1 t. dz dx + dy y sinx + 4y)0t + 4) sinx + 4y) 1t ) 0t + 4t ) sinx