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Non-circular gear

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rolling together without slip. In the case of non-circular gears, those circles are replaced with anything different from a circle. For this reason NCGs in most cases are not round, but round NCGs that look like regular gears are also possible (small ratio variations result from meshing area
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Each wheel must be cyclic in its angular coordinates. If the shape of the first wheel is known, the shape of the second can often be found using the above equations. If the relationship between the angles is specified, the shapes of both wheels can often be determined analytically as well.
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Assuming that the point of contact lies on the line connecting the axles, in order for the gears to touch without slipping, the velocity of each wheel must be equal at the point of contact and perpendicular to the line connecting the axles, which implies that:
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distance, could prove impossible to support, and such gears require very tight manufacturing tolerances and assembling problems arise. Because of complicated
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Noncircular Gears: Design and Generation by Faydor L. Litvin, Alfonso Fuentes-Aznar, Ignacio Gonzalez-Perez, and Kenichi Hayasaka
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Generally, NCGs should meet all the requirements of regular gearing but in some cases, for example variable
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describe the rotation of the first and second gears respectively. This equation can be formally solved as:
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when analyzing this problem. Assuming the radius of the first gear wheel is known as a function of
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design with special characteristics and purpose. While a regular gear is optimized to transmit
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Ignoring the gear teeth for the moment (i.e. assuming the gear teeth are very small), let
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be the radius of the second gear wheel as a function of angle from its axis of rotation
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be the radius of the first gear wheel as a function of angle from the axis of rotation
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Laczik - Design and Manufacturing of Non-Circular Gears by Given Transfer Function
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Maurice Lacroix Masterpiece Regulateur Roue Carree. Squaring the Circle.
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to another engaged member with minimum noise and wear and with maximum
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Zarebski I., Salacinski T.: Designing of non-circular gears
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and more. Common applications include textile machines,
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Kinematic Models for Design Digital Library (KMODDL)
414:It is more convenient to use the circular variable 887: 852: 690: 663: 633: 485: 442: 399: 324: 242: 215: 172: 145: 1333: 55:, a non-circular gear's main objective might be 967:Historic Video of Non-Circular Gears on YouTube 992:Laczik- Involute Profile of Non-Circular Gears 926:Laczik- Involute Profile of Non-Circular Gears 74:A regular gear pair can be represented as two 1032: 105: 1039: 1025: 1002:A paper on designing of non-circular gears 102:technology is used instead of generation. 937: 935: 933: 820: 601: 476: 383: 356: 321: 26: 18: 910: 908: 1334: 930: 1020: 905: 69:continuously variable transmissions 16:Gear in a shape other than a circle 13: 1200:Continuously variable transmission 950: 216:{\displaystyle r_{2}(\theta _{2})} 146:{\displaystyle r_{1}(\theta _{1})} 14: 1353: 960: 486:{\displaystyle dz=iz\,d\theta } 919: 895:is a constant of integration. 882: 876: 814: 801: 780: 767: 745: 739: 727: 714: 595: 582: 561: 548: 443:{\displaystyle z=e^{i\theta }} 312: 299: 283: 270: 210: 197: 140: 127: 100:electrical discharge machining 59:variations, axle displacement 1: 1077:Epicyclic (planetary) gearing 898: 454:, and using the relationship 7: 243:{\displaystyle \theta _{2}} 173:{\displaystyle \theta _{1}} 10: 1358: 1013: (archived 2014-05-09) 988: (archived 2013-06-05) 1321:Spur gear corrected tooth 1278: 1256: 1220: 1213: 1167: 1146: 1105: 1054: 1046: 31:Another non-circular gear 23:Non-circular gear example 106:Mathematical description 90:, NCGs are most likely 889: 888:{\displaystyle \ln(K)} 854: 692: 665: 635: 487: 444: 401: 326: 244: 217: 174: 147: 32: 24: 890: 855: 693: 691:{\displaystyle z_{2}} 666: 664:{\displaystyle z_{1}} 636: 488: 445: 402: 327: 245: 218: 175: 148: 30: 22: 1243:Shaft-driven bicycle 972:The Eye of an Artist 867: 705: 675: 648: 500: 458: 418: 343: 257: 227: 184: 157: 114: 1082:Sun and planet gear 982:The Gear Oscillator 1311:Gear manufacturing 1147:Geartooth profiles 885: 850: 688: 661: 631: 483: 440: 397: 322: 240: 213: 170: 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gearing 1163: 1142: 1101: 1092:Cycloidal drive 1072:Rack and pinion 1050: 1045: 1011:Wayback Machine 986:Wayback Machine 963: 953: 951:Further reading 948: 947: 940: 931: 924: 920: 913: 906: 901: 868: 865: 864: 842: 838: 831: 827: 823: 821: 808: 804: 795: 791: 784: 774: 770: 761: 757: 756: 754: 721: 717: 706: 703: 702: 682: 678: 676: 673: 672: 655: 651: 649: 646: 645: 623: 619: 612: 608: 604: 602: 589: 585: 576: 572: 565: 555: 551: 542: 538: 537: 535: 524: 520: 513: 509: 505: 503: 501: 498: 497: 459: 456: 455: 431: 427: 419: 416: 415: 391: 387: 377: 373: 364: 360: 350: 346: 344: 341: 340: 306: 302: 293: 289: 277: 273: 264: 260: 258: 255: 254: 234: 230: 228: 225: 224: 204: 200: 191: 187: 185: 182: 181: 164: 160: 158: 155: 154: 134: 130: 121: 117: 115: 112: 111: 108: 43:) is a special 17: 12: 11: 5: 1355: 1345: 1344: 1327: 1326: 1324: 1323: 1318: 1313: 1308: 1303: 1298: 1293: 1288: 1282: 1280: 1276: 1275: 1272: 1271: 1269: 1268: 1262: 1260: 1254: 1253: 1251: 1250: 1245: 1240: 1235: 1230: 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1291:Leadscrew 1168:Mechanics 874:⁡ 789:− 752:∫ 737:⁡ 712:⁡ 570:− 481:θ 436:θ 389:θ 362:θ 304:θ 275:θ 232:θ 202:θ 162:θ 132:θ 1336:Category 1279:See also 1258:Horology 1248:Sprocket 1238:Hub gear 1221:Bicycles 1214:Examples 1185:Coupling 1154:Involute 88:geometry 67:, CVTs ( 1159:Cycloid 1133:Helical 1055:Systems 1009:at the 984:at the 96:molding 76:circles 1228:Cogset 1205:Offset 1106:Shapes 863:where 644:where 49:torque 1342:Gears 1190:Train 1123:Crown 1118:Bevel 1048:Gears 57:ratio 1113:Spur 671:and 94:and 84:axle 45:gear 98:or 41:NCG 1338:: 932:^ 907:^ 871:ln 734:ln 709:ln 35:A 1040:e 1033:t 1026:v 883:) 880:K 877:( 844:1 840:z 833:1 829:z 825:d 815:) 810:1 806:z 802:( 797:1 793:r 786:a 781:) 776:1 772:z 768:( 763:1 759:r 749:+ 746:) 743:K 740:( 731:= 728:) 723:2 719:z 715:( 684:2 680:z 657:1 653:z 625:1 621:z 614:1 610:z 606:d 596:) 591:1 587:z 583:( 578:1 574:r 567:a 562:) 557:1 553:z 549:( 544:1 540:r 533:= 526:2 522:z 515:2 511:z 507:d 478:d 474:z 471:i 468:= 465:z 462:d 452:z 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Index



gear
torque
efficiency
ratio
oscillations
potentiometers
continuously variable transmissions
circles
axle
geometry
spur gears
molding
electrical discharge machining


Zarebski I., Salacinski T.: Designing of non-circular gears
Laczik- Involute Profile of Non-Circular Gears



Laczik - Design and Manufacturing of Non-Circular Gears by Given Transfer Function
Historic Video of Non-Circular Gears on YouTube
The Eye of an Artist
Kinematic Models for Design Digital Library (KMODDL)
The Gear Oscillator
Wayback Machine
Laczik- Involute Profile of Non-Circular Gears
"Gear geometry and applied theory" by Faydor L. Litvin and Alfonso Fuentes

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