286:
1784:
65:
1721:
1486:
407:
245:
76:
38:
1492:
1257:
2769:
784:
619:
1241:
262:, which is easier to machine than square threads. They are not as efficient as square threads, due to the increased friction induced by the thread angle. Acme threads are generally also stronger than square threads due to their trapezoidal thread profile, which provides greater load-bearing capabilities.
414:
The torque required to lift or lower a load can be calculated by "unwrapping" one revolution of a thread. This is most easily described for a square or buttress thread as the thread angle is 0 and has no bearing on the calculations. The unwrapped thread forms a right angle triangle where the base is
445:
long and the height is the lead (pictured to the right). The force of the load is directed downward, the normal force is perpendicular to the hypotenuse of the triangle, the frictional force is directed in the opposite direction of the direction of motion (perpendicular to the normal force or along
332:
The disadvantages are that most are not very efficient. Due to this low efficiency, they cannot be used in continuous power transmission applications. They also have a high degree of friction on the threads, which can wear the threads out quickly. For square threads, the nut must be replaced; for
209:
because they have more friction between the threads. Their threads are designed to induce this friction to keep the fastener from loosening. Leadscrews, on the other hand, are designed to minimize friction. Therefore, in most commercial and industrial use, V-threads are avoided for leadscrew use.
184:
leadscrew overcomes many of the disadvantages of a normal leadscrew, having high positional accuracy, very low friction, and very low wear, but requires continuous supply of high-pressure fluid and high-precision manufacture, leading to significantly greater cost than most other linear motion
1716:{\displaystyle T_{\text{lower}}={\frac {Fd_{\text{m}}}{2}}\left({\frac {\pi \mu d_{\text{m}}\sec {\alpha }-l}{\pi d_{\text{m}}+\mu l\sec {\alpha }}}\right)={\frac {Fd_{\text{m}}}{2}}\left({\frac {\mu \sec {\alpha }-\tan {\lambda }}{1+\mu \sec {\alpha }\tan {\lambda }}}\right)}
1481:{\displaystyle T_{\text{raise}}={\frac {Fd_{\text{m}}}{2}}\left({\frac {l+\pi \mu d_{\text{m}}\sec {\alpha }}{\pi d_{\text{m}}-\mu l\sec {\alpha }}}\right)={\frac {Fd_{\text{m}}}{2}}\left({\frac {\mu \sec {\alpha }+\tan {\lambda }}{1-\mu \sec {\alpha }\tan {\lambda }}}\right)}
625:
460:
1750:
If the leadscrew has a collar which the load rides on, then the frictional forces between the interface must be accounted for in the torque calculations as well. For the following equation the load is assumed to be concentrated at the mean collar diameter
2002:
1113:
276:
Buttress threads are of a triangular shape. These are used where the load force on the screw is only applied in one direction. They are as efficient as square threads in these applications, but are easier to manufacture.
1068:
equation, it can be found that the screw is self-locking when the coefficient of friction is greater than the tangent of the lead angle. An equivalent comparison is when the friction angle is greater than the lead angle
1849:
2327:
2563:
1251:
For screws that have a thread angle other than zero, such as a trapezoidal thread, this must be compensated as it increases the frictional forces. The equations below take this into account:
779:{\displaystyle T_{\text{lower}}={\frac {Fd_{\text{m}}}{2}}\left({\frac {\pi \mu d_{\text{m}}-l}{\pi d_{\text{m}}+\mu l}}\right)={\frac {Fd_{\text{m}}}{2}}\tan {\left(\phi -\lambda \right)}}
614:{\displaystyle T_{\text{raise}}={\frac {Fd_{\text{m}}}{2}}\left({\frac {l+\pi \mu d_{\text{m}}}{\pi d_{\text{m}}-\mu l}}\right)={\frac {Fd_{\text{m}}}{2}}\tan {\left(\phi +\lambda \right)}}
1093:
1066:
443:
2069:
2040:
1879:
1916:
2382:
1906:
1776:
941:
1035:
1745:
1236:{\displaystyle {\mbox{efficiency}}={\frac {T_{0}}{T_{\text{raise}}}}={\frac {Fl}{2\pi T_{\text{raise}}}}={\frac {\tan {\lambda }}{\tan {\left(\phi +\lambda \right)}}}}
1009:
964:
2252:. The critical speed is the speed that excites the natural frequency of the screw. For a steel leadscrew or steel ballscrew, the critical speed is approximately
2674:
2652:
2630:
2608:
2585:
2492:
2470:
2448:
2426:
2404:
2353:
986:
912:
890:
165:(also called half nut) which allows the nut to be disengaged from the threads and moved axially, independently of the screw's rotation, when needed (such as in
2764:, Pflager, William W., "Hydrostatic nut and lead screw assembly, and method of forming said nut", published 1996-03-19, assigned to
236:, so they are often used for screws that carry high power; however, they are also the most difficult to machine, and are thus the most expensive.
2932:
1908:
is the mean collar diameter. For collars that use thrust bearings, the frictional loss is negligible and the above equation can be ignored.
1792:
127:
energy losses compared to other linkages. They are not typically used to carry high power, but more for intermittent use in low power
2258:
3072:
Originally published in 1998; content updated with each print run, similar to a "revised edition". Currently in the fourth print run.
2503:
2958:
3088:
3064:
3045:
2983:
2908:
166:
3285:
116:
3265:
3124:
2248:
The running speed for a leadscrew (or ball screw) is typically limited to, at most, 80% of the calculated
3007:
1072:
17:
2761:
1997:{\displaystyle \eta ={\frac {\cos \alpha \ -\ \mu \tan \lambda }{\cos \alpha \ +\ \mu \cot \lambda }}}
1044:
418:
3406:
2047:
2018:
1857:
155:
285:
2360:
1884:
1754:
919:
3260:
206:
1019:
1729:
100:
1787:
Plot of square lead screw efficiency against lead angle for different coefficients of friction
2691:
993:
229:
948:
3328:
104:
8:
3172:
3167:
3117:
3396:
2926:
2659:
2637:
2615:
2593:
2570:
2477:
2455:
2433:
2411:
2389:
2338:
971:
897:
875:
223:
2955:
210:
Nevertheless, V-threads are sometimes successfully used as leadscrews, for example on
3386:
3213:
3182:
3162:
3084:
3060:
3057:
Tabletop
Machining: A Basic Approach to Making Small Parts on Miniature Machine Tools
3041:
2989:
2979:
2914:
2904:
1012:
451:
3223:
387:
253:
144:
2567:
where the variables are identical to above, but the values are in millimetres and
3427:
3280:
3177:
3157:
3078:
3035:
2962:
381:
271:
132:
48:
3290:
3110:
2249:
1783:
154:
Leadscrews are manufactured in the same way as other thread forms: they may be
53:
2918:
356:(sometimes categorized as types of leadscrew rather than in contradistinction)
3421:
3270:
3239:
2993:
2765:
181:
148:
112:
69:
58:
450:
in the direction opposite the direction of the frictional force. Using this
3244:
353:
290:
259:
194:
136:
120:
42:
3391:
3351:
3077:
Shigley, Joseph E.; Mischke, Charles R.; Budynas, Richard Gordon (2003),
2126:
Safe running speeds for various nut materials and loads on a steel screw
966:= coefficient of friction (common values are found in the adjacent table)
359:
140:
64:
228:
Square threads are named after their square geometry. They are the most
3371:
3318:
3275:
3208:
3203:
3152:
2686:
377:
367:
363:
349:
211:
31:
1844:{\displaystyle T_{\text{c}}={\frac {F\mu _{\text{c}}d_{\text{c}}}{2}}}
3401:
3381:
3198:
3147:
2696:
334:
162:
3343:
3333:
3323:
3218:
391:
233:
128:
124:
108:
1881:
is the coefficient of friction between the collar on the load and
151:. Leadscrews are a common component in electric linear actuators.
1911:
Efficiency for non-zero thread angles can be written as follows:
1107:
The efficiency, calculated using the torque equations above, is:
2322:{\displaystyle N={(4.76\times 10^{6})d_{\text{r}}C \over L^{2}}}
30:
For worm gear used with circular gear for rotary reduction, see
3313:
454:
the torque required to lift or lower a load can be calculated:
205:
V-threads are less suitable for leadscrews than others such as
244:
115:. Because of the large area of sliding contact between their
2976:
Electromechanical motion systems : design and simulation
2715:
2558:{\displaystyle N={\frac {Cd_{\text{r}}\times 10^{7}}{L^{2}}}}
406:
289:
Leadscrews are used to raise and lower the front door of the
170:
75:
37:
2956:"Acme & lead screw assembly glossary and technical data"
131:
and positioner mechanisms. Leadscrews are commonly used in
3133:
446:
the hypotenuse), and an imaginary "effort" force is acting
373:
174:
3102:
2903:(Second ed.). Oxford, United Kingdom. p. 803.
3008:"Critical Speed - August Steinmeyer GmbH & Co. KG"
1118:
3076:
2662:
2640:
2618:
2596:
2573:
2506:
2480:
2458:
2436:
2414:
2392:
2384:= smallest (root) diameter of the leadscrew in inches
2363:
2341:
2261:
2050:
2021:
1919:
1887:
1860:
1795:
1757:
1732:
1495:
1260:
1116:
1075:
1047:
1022:
996:
974:
951:
922:
900:
878:
628:
463:
421:
193:
Power screws are classified by the geometry of their
239:
2668:
2646:
2624:
2602:
2579:
2557:
2486:
2464:
2442:
2420:
2398:
2376:
2347:
2321:
2063:
2034:
1996:
1900:
1873:
1843:
1770:
1739:
1715:
1480:
1235:
1087:
1060:
1029:
1003:
980:
958:
935:
906:
884:
778:
613:
437:
173:). A split nut can also be used to compensate for
79:Floppy disc drive with leadscrew and stepper motor
3419:
345:Alternatives to actuation by leadscrew include:
280:
2885:
2883:
790:Coefficient of friction for leadscrew threads
3118:
2855:
2853:
2851:
2781:
2779:
2735:
2733:
328:Most are self-locking (cannot be back-driven)
2814:
2812:
2978:. Chichester, England: Wiley. p. 121.
2880:
2406:= length between bearing supports in inches
2007:Coefficient of friction for thrust collars
3125:
3111:
3059:, Vista, California, USA: Sherline, Inc.,
2931:: CS1 maint: location missing publisher (
2848:
2776:
2730:
2809:
2747:
2745:
2124:
1736:
1099:, or lower under the weight of the load.
1095:). When this is not true, the screw will
1026:
1000:
955:
788:
3033:
2899:Childs, Peter R. N. (24 November 2018).
2610:= 3.9 for fixed-free supports
2472:= 1.47 for one end fixed, one end simple
2005:
1782:
1246:
405:
337:may be used to compensate for the wear.
284:
243:
74:
63:
36:
2760:
14:
3420:
3054:
2973:
2901:Mechanical design engineering handbook
2898:
2794:
2742:
410:Diagram of an "unwrapped" screw thread
161:A lead screw is sometimes used with a
27:Screw used as a linkage in a mechanism
3106:
2428:= .36 for one end fixed, one end free
177:by compressing the parts of the nut.
2654:= 18.7 for fixed-supported structure
297:The advantages of a leadscrew are:
24:
3286:Continuously variable transmission
2498:Alternatively using metric units:
316:Precise and accurate linear motion
265:
25:
3439:
3098:
1088:{\displaystyle \phi >\lambda }
2974:Moritz, Frederick G. F. (2014).
2120:
1061:{\displaystyle T_{\text{lower}}}
438:{\displaystyle \pi d_{\text{m}}}
240:Acme thread / Trapezoidal thread
217:
3027:
3000:
2967:
2948:
2939:
2892:
2871:
2862:
2839:
2830:
2064:{\displaystyle \mu _{\text{c}}}
2035:{\displaystyle \mu _{\text{c}}}
1874:{\displaystyle \mu _{\text{c}}}
340:
2821:
2800:
2788:
2754:
2708:
2632:= 12.1 for both ends supported
2290:
2271:
1747:is one half the thread angle.
301:Large load carrying capability
13:
1:
3163:Epicyclic (planetary) gearing
3083:(7th ed.), McGraw Hill,
3080:Mechanical Engineering Design
2717:Ball Screws & Lead screws
2702:
1102:
135:, machine slides (such as in
68:DVD drive with leadscrew and
2377:{\displaystyle d_{\text{r}}}
1901:{\displaystyle d_{\text{c}}}
1771:{\displaystyle d_{\text{c}}}
936:{\displaystyle d_{\text{m}}}
401:
281:Advantages and disadvantages
7:
2680:
2450:= 1.00 for both ends simple
2142:
2139:
2136:
2133:
2130:
200:
107:in a machine, to translate
10:
3444:
3037:Design of Machine Elements
2676:= 27.2 for both ends fixed
2494:= 2.23 for both ends fixed
2086:Hardened steel / cast iron
1030:{\displaystyle \lambda \,}
319:Smooth and quiet operation
313:Large mechanical advantage
269:
251:
221:
29:
3407:Spur gear corrected tooth
3364:
3342:
3306:
3299:
3253:
3232:
3191:
3140:
3132:
2156:
1740:{\displaystyle \alpha \,}
797:
794:
258:Acme threads have a 29°
188:
2355:= critical speed in RPM
2108:Hardened steel / bronze
1004:{\displaystyle \phi \,}
397:Piezoelectric actuation
333:trapezoidal threads, a
325:Minimal number of parts
3034:Bhandari, V B (2007),
2954:Nook Industries, Inc.
2877:Bhandari, pp. 211–212.
2827:Bhandari, pp. 207–208.
2670:
2648:
2626:
2604:
2581:
2559:
2488:
2466:
2444:
2422:
2400:
2378:
2349:
2323:
2075:Soft steel / cast iron
2065:
2036:
1998:
1902:
1875:
1845:
1788:
1772:
1741:
1717:
1482:
1237:
1089:
1062:
1031:
1005:
982:
960:
959:{\displaystyle \mu \,}
937:
908:
886:
780:
615:
439:
411:
294:
249:
167:single-point threading
156:rolled, cut, or ground
80:
72:
61:
2692:Fine adjustment screw
2671:
2649:
2627:
2605:
2582:
2560:
2489:
2467:
2445:
2423:
2401:
2379:
2350:
2324:
2182:1,800–2,500 psi
2165:1,600–2,500 psi
2151:2,500–3,500 psi
2066:
2037:
1999:
1903:
1876:
1846:
1786:
1773:
1742:
1718:
1483:
1247:Non-zero thread angle
1238:
1090:
1063:
1032:
1006:
983:
961:
938:
909:
887:
781:
616:
440:
409:
288:
247:
78:
67:
40:
3329:Shaft-driven bicycle
3055:Martin, Joe (2004),
3040:, Tata McGraw-Hill,
2660:
2638:
2616:
2594:
2571:
2504:
2478:
2456:
2434:
2412:
2390:
2361:
2339:
2259:
2048:
2019:
2012:Material combination
1917:
1885:
1858:
1793:
1755:
1730:
1493:
1258:
1114:
1073:
1045:
1020:
994:
972:
949:
920:
898:
876:
626:
461:
419:
307:Simplicity of design
45:used in leadscrews:
3168:Sun and planet gear
2225:0.10–0.20 m/s
2216:600–1,000 psi
2208:0.10–0.20 m/s
2199:800–1,400 psi
2127:
2097:Soft steel / bronze
2008:
914:= load on the screw
791:
310:Ease of manufacture
293:Freighter aircraft.
232:, having the least
91:), also known as a
3397:Gear manufacturing
3233:Geartooth profiles
3012:www.steinmeyer.com
2961:2008-07-05 at the
2766:Western Atlas Inc.
2666:
2644:
2622:
2600:
2577:
2555:
2484:
2462:
2440:
2418:
2396:
2374:
2345:
2319:
2125:
2061:
2032:
2006:
1994:
1898:
1871:
1841:
1789:
1768:
1737:
1713:
1478:
1233:
1122:
1085:
1058:
1027:
1001:
978:
956:
933:
904:
882:
834:Steel, machine oil
789:
776:
611:
435:
412:
295:
250:
224:Square thread form
81:
73:
62:
3415:
3414:
3360:
3359:
3183:Non-circular gear
3148:Spur gear systems
3090:978-0-07-252036-1
3066:978-0-9665433-0-8
3047:978-0-07-061141-2
2985:978-1-118-35967-9
2910:978-0-08-102368-6
2889:Bhandari, p. 213.
2868:Bhandari, p. 209.
2845:Bhandari, p. 208.
2806:Bhandari, p. 204.
2785:Bhandari, p. 203.
2739:Bhandari, p. 202.
2669:{\displaystyle C}
2647:{\displaystyle C}
2625:{\displaystyle C}
2603:{\displaystyle C}
2580:{\displaystyle C}
2553:
2526:
2487:{\displaystyle C}
2465:{\displaystyle C}
2443:{\displaystyle C}
2421:{\displaystyle C}
2399:{\displaystyle L}
2371:
2348:{\displaystyle N}
2317:
2300:
2246:
2245:
2233:150–240 psi
2185:120–170 bar
2168:110–170 bar
2154:170–240 bar
2137:Safe loads (bar)
2134:Safe loads (psi)
2118:
2117:
2058:
2029:
1992:
1978:
1972:
1946:
1940:
1895:
1868:
1839:
1832:
1822:
1803:
1765:
1707:
1636:
1629:
1607:
1583:
1551:
1529:
1522:
1503:
1472:
1401:
1394:
1372:
1348:
1322:
1294:
1287:
1268:
1231:
1182:
1178:
1149:
1146:
1121:
1055:
1013:angle of friction
981:{\displaystyle l}
930:
907:{\displaystyle F}
885:{\displaystyle T}
867:
866:
747:
740:
718:
705:
684:
662:
655:
636:
582:
575:
553:
540:
525:
497:
490:
471:
452:free-body diagram
432:
390:actuation (e.g.,
97:translation screw
16:(Redirected from
3435:
3304:
3303:
3127:
3120:
3113:
3104:
3103:
3093:
3069:
3050:
3022:
3021:
3019:
3018:
3004:
2998:
2997:
2971:
2965:
2952:
2946:
2945:Shigley, p. 407.
2943:
2937:
2936:
2930:
2922:
2896:
2890:
2887:
2878:
2875:
2869:
2866:
2860:
2859:Shigley, p. 403.
2857:
2846:
2843:
2837:
2836:Shigley, p. 408.
2834:
2828:
2825:
2819:
2818:Shigley, p. 402.
2816:
2807:
2804:
2798:
2792:
2786:
2783:
2774:
2773:
2772:
2768:
2758:
2752:
2751:Shigley, p. 400.
2749:
2740:
2737:
2728:
2726:
2725:
2724:
2712:
2675:
2673:
2672:
2667:
2653:
2651:
2650:
2645:
2631:
2629:
2628:
2623:
2609:
2607:
2606:
2601:
2586:
2584:
2583:
2578:
2564:
2562:
2561:
2556:
2554:
2552:
2551:
2542:
2541:
2540:
2528:
2527:
2524:
2514:
2493:
2491:
2490:
2485:
2471:
2469:
2468:
2463:
2449:
2447:
2446:
2441:
2427:
2425:
2424:
2419:
2405:
2403:
2402:
2397:
2383:
2381:
2380:
2375:
2373:
2372:
2369:
2354:
2352:
2351:
2346:
2328:
2326:
2325:
2320:
2318:
2316:
2315:
2306:
2302:
2301:
2298:
2289:
2288:
2269:
2128:
2070:
2068:
2067:
2062:
2060:
2059:
2056:
2041:
2039:
2038:
2033:
2031:
2030:
2027:
2009:
2003:
2001:
2000:
1995:
1993:
1991:
1976:
1970:
1959:
1944:
1938:
1927:
1907:
1905:
1904:
1899:
1897:
1896:
1893:
1880:
1878:
1877:
1872:
1870:
1869:
1866:
1850:
1848:
1847:
1842:
1840:
1835:
1834:
1833:
1830:
1824:
1823:
1820:
1810:
1805:
1804:
1801:
1777:
1775:
1774:
1769:
1767:
1766:
1763:
1746:
1744:
1743:
1738:
1722:
1720:
1719:
1714:
1712:
1708:
1706:
1705:
1694:
1673:
1672:
1658:
1643:
1637:
1632:
1631:
1630:
1627:
1617:
1612:
1608:
1606:
1605:
1585:
1584:
1581:
1571:
1564:
1553:
1552:
1549:
1536:
1530:
1525:
1524:
1523:
1520:
1510:
1505:
1504:
1501:
1487:
1485:
1484:
1479:
1477:
1473:
1471:
1470:
1459:
1438:
1437:
1423:
1408:
1402:
1397:
1396:
1395:
1392:
1382:
1377:
1373:
1371:
1370:
1350:
1349:
1346:
1336:
1335:
1324:
1323:
1320:
1301:
1295:
1290:
1289:
1288:
1285:
1275:
1270:
1269:
1266:
1242:
1240:
1239:
1234:
1232:
1230:
1229:
1228:
1224:
1201:
1200:
1188:
1183:
1181:
1180:
1179:
1176:
1163:
1155:
1150:
1148:
1147:
1144:
1138:
1137:
1128:
1123:
1119:
1094:
1092:
1091:
1086:
1067:
1065:
1064:
1059:
1057:
1056:
1053:
1036:
1034:
1033:
1028:
1010:
1008:
1007:
1002:
987:
985:
984:
979:
965:
963:
962:
957:
942:
940:
939:
934:
932:
931:
928:
913:
911:
910:
905:
891:
889:
888:
883:
792:
785:
783:
782:
777:
775:
774:
770:
748:
743:
742:
741:
738:
728:
723:
719:
717:
707:
706:
703:
693:
686:
685:
682:
669:
663:
658:
657:
656:
653:
643:
638:
637:
634:
620:
618:
617:
612:
610:
609:
605:
583:
578:
577:
576:
573:
563:
558:
554:
552:
542:
541:
538:
528:
527:
526:
523:
504:
498:
493:
492:
491:
488:
478:
473:
472:
469:
444:
442:
441:
436:
434:
433:
430:
254:Acme thread form
214:and micromills.
133:linear actuators
21:
3443:
3442:
3438:
3437:
3436:
3434:
3433:
3432:
3418:
3417:
3416:
3411:
3356:
3338:
3295:
3281:Bicycle gearing
3249:
3228:
3187:
3178:Cycloidal drive
3158:Rack and pinion
3136:
3131:
3101:
3091:
3067:
3048:
3030:
3025:
3016:
3014:
3006:
3005:
3001:
2986:
2972:
2968:
2963:Wayback Machine
2953:
2949:
2944:
2940:
2924:
2923:
2911:
2897:
2893:
2888:
2881:
2876:
2872:
2867:
2863:
2858:
2849:
2844:
2840:
2835:
2831:
2826:
2822:
2817:
2810:
2805:
2801:
2793:
2789:
2784:
2777:
2770:
2759:
2755:
2750:
2743:
2738:
2731:
2722:
2720:
2714:
2713:
2709:
2705:
2683:
2661:
2658:
2657:
2639:
2636:
2635:
2617:
2614:
2613:
2595:
2592:
2591:
2587:is as follows:
2572:
2569:
2568:
2547:
2543:
2536:
2532:
2523:
2519:
2515:
2513:
2505:
2502:
2501:
2479:
2476:
2475:
2457:
2454:
2453:
2435:
2432:
2431:
2413:
2410:
2409:
2391:
2388:
2387:
2368:
2364:
2362:
2359:
2358:
2340:
2337:
2336:
2311:
2307:
2297:
2293:
2284:
2280:
2270:
2268:
2260:
2257:
2256:
2236:10–17 bar
2219:41–69 bar
2202:55–97 bar
2123:
2055:
2051:
2049:
2046:
2045:
2026:
2022:
2020:
2017:
2016:
1960:
1928:
1926:
1918:
1915:
1914:
1892:
1888:
1886:
1883:
1882:
1865:
1861:
1859:
1856:
1855:
1829:
1825:
1819:
1815:
1811:
1809:
1800:
1796:
1794:
1791:
1790:
1762:
1758:
1756:
1753:
1752:
1731:
1728:
1727:
1701:
1690:
1674:
1668:
1654:
1644:
1642:
1638:
1626:
1622:
1618:
1616:
1601:
1580:
1576:
1572:
1560:
1548:
1544:
1537:
1535:
1531:
1519:
1515:
1511:
1509:
1500:
1496:
1494:
1491:
1490:
1466:
1455:
1439:
1433:
1419:
1409:
1407:
1403:
1391:
1387:
1383:
1381:
1366:
1345:
1341:
1337:
1331:
1319:
1315:
1302:
1300:
1296:
1284:
1280:
1276:
1274:
1265:
1261:
1259:
1256:
1255:
1249:
1214:
1210:
1209:
1202:
1196:
1189:
1187:
1175:
1171:
1164:
1156:
1154:
1143:
1139:
1133:
1129:
1127:
1117:
1115:
1112:
1111:
1105:
1074:
1071:
1070:
1052:
1048:
1046:
1043:
1042:
1021:
1018:
1017:
995:
992:
991:
973:
970:
969:
950:
947:
946:
943:= mean diameter
927:
923:
921:
918:
917:
899:
896:
895:
877:
874:
873:
760:
756:
755:
737:
733:
729:
727:
702:
698:
694:
681:
677:
670:
668:
664:
652:
648:
644:
642:
633:
629:
627:
624:
623:
595:
591:
590:
572:
568:
564:
562:
537:
533:
529:
522:
518:
505:
503:
499:
487:
483:
479:
477:
468:
464:
462:
459:
458:
429:
425:
420:
417:
416:
404:
388:Electromagnetic
382:rack-and-pinion
343:
322:Low maintenance
283:
274:
272:Buttress thread
268:
266:Buttress thread
256:
242:
226:
220:
203:
191:
117:male and female
56:
51:
49:buttress thread
46:
41:Three types of
35:
28:
23:
22:
15:
12:
11:
5:
3441:
3431:
3430:
3413:
3412:
3410:
3409:
3404:
3399:
3394:
3389:
3384:
3379:
3374:
3368:
3366:
3362:
3361:
3358:
3357:
3355:
3354:
3348:
3346:
3340:
3339:
3337:
3336:
3331:
3326:
3321:
3316:
3310:
3308:
3301:
3297:
3296:
3294:
3293:
3288:
3283:
3278:
3273:
3268:
3263:
3257:
3255:
3251:
3250:
3248:
3247:
3242:
3236:
3234:
3230:
3229:
3227:
3226:
3221:
3216:
3211:
3206:
3201:
3195:
3193:
3189:
3188:
3186:
3185:
3180:
3175:
3173:Harmonic drive
3170:
3165:
3160:
3155:
3150:
3144:
3142:
3138:
3137:
3130:
3129:
3122:
3115:
3107:
3100:
3099:External links
3097:
3096:
3095:
3089:
3074:
3065:
3052:
3046:
3029:
3026:
3024:
3023:
2999:
2984:
2966:
2947:
2938:
2909:
2891:
2879:
2870:
2861:
2847:
2838:
2829:
2820:
2808:
2799:
2797:, p. 266.
2787:
2775:
2753:
2741:
2729:
2706:
2704:
2701:
2700:
2699:
2694:
2689:
2682:
2679:
2678:
2677:
2665:
2655:
2643:
2633:
2621:
2611:
2599:
2576:
2550:
2546:
2539:
2535:
2531:
2522:
2518:
2512:
2509:
2496:
2495:
2483:
2473:
2461:
2451:
2439:
2429:
2417:
2407:
2395:
2385:
2367:
2356:
2344:
2330:
2329:
2314:
2310:
2305:
2296:
2292:
2287:
2283:
2279:
2276:
2273:
2267:
2264:
2250:critical speed
2244:
2243:
2242:0.25 m/s
2240:
2237:
2234:
2231:
2227:
2226:
2223:
2220:
2217:
2214:
2210:
2209:
2206:
2203:
2200:
2197:
2193:
2192:
2191:0.04 m/s
2189:
2186:
2183:
2180:
2176:
2175:
2174:0.05 m/s
2172:
2169:
2166:
2163:
2159:
2158:
2155:
2152:
2149:
2145:
2144:
2141:
2138:
2135:
2132:
2122:
2119:
2116:
2115:
2112:
2109:
2105:
2104:
2101:
2098:
2094:
2093:
2090:
2087:
2083:
2082:
2079:
2076:
2072:
2071:
2054:
2042:
2025:
2013:
1990:
1987:
1984:
1981:
1975:
1969:
1966:
1963:
1958:
1955:
1952:
1949:
1943:
1937:
1934:
1931:
1925:
1922:
1891:
1864:
1852:
1851:
1838:
1828:
1818:
1814:
1808:
1799:
1761:
1735:
1724:
1723:
1711:
1704:
1700:
1697:
1693:
1689:
1686:
1683:
1680:
1677:
1671:
1667:
1664:
1661:
1657:
1653:
1650:
1647:
1641:
1635:
1625:
1621:
1615:
1611:
1604:
1600:
1597:
1594:
1591:
1588:
1579:
1575:
1570:
1567:
1563:
1559:
1556:
1547:
1543:
1540:
1534:
1528:
1518:
1514:
1508:
1499:
1488:
1476:
1469:
1465:
1462:
1458:
1454:
1451:
1448:
1445:
1442:
1436:
1432:
1429:
1426:
1422:
1418:
1415:
1412:
1406:
1400:
1390:
1386:
1380:
1376:
1369:
1365:
1362:
1359:
1356:
1353:
1344:
1340:
1334:
1330:
1327:
1318:
1314:
1311:
1308:
1305:
1299:
1293:
1283:
1279:
1273:
1264:
1248:
1245:
1244:
1243:
1227:
1223:
1220:
1217:
1213:
1208:
1205:
1199:
1195:
1192:
1186:
1174:
1170:
1167:
1162:
1159:
1153:
1142:
1136:
1132:
1126:
1104:
1101:
1084:
1081:
1078:
1051:
1039:
1038:
1025:
1015:
999:
989:
977:
967:
954:
944:
926:
915:
903:
893:
881:
865:
864:
861:
858:
855:
852:
848:
847:
844:
841:
838:
835:
831:
830:
827:
824:
821:
818:
814:
813:
810:
807:
804:
800:
799:
796:
795:Screw material
787:
786:
773:
769:
766:
763:
759:
754:
751:
746:
736:
732:
726:
722:
716:
713:
710:
701:
697:
692:
689:
680:
676:
673:
667:
661:
651:
647:
641:
632:
621:
608:
604:
601:
598:
594:
589:
586:
581:
571:
567:
561:
557:
551:
548:
545:
536:
532:
521:
517:
514:
511:
508:
502:
496:
486:
482:
476:
467:
428:
424:
403:
400:
399:
398:
395:
385:
376:trains (e.g.,
371:
357:
342:
339:
330:
329:
326:
323:
320:
317:
314:
311:
308:
305:
302:
282:
279:
270:Main article:
267:
264:
252:Main article:
241:
238:
222:Main article:
219:
216:
202:
199:
190:
187:
109:turning motion
26:
9:
6:
4:
3:
2:
3440:
3429:
3426:
3425:
3423:
3408:
3405:
3403:
3400:
3398:
3395:
3393:
3390:
3388:
3385:
3383:
3380:
3378:
3375:
3373:
3370:
3369:
3367:
3363:
3353:
3350:
3349:
3347:
3345:
3341:
3335:
3332:
3330:
3327:
3325:
3322:
3320:
3317:
3315:
3312:
3311:
3309:
3305:
3302:
3298:
3292:
3289:
3287:
3284:
3282:
3279:
3277:
3274:
3272:
3269:
3267:
3264:
3262:
3259:
3258:
3256:
3252:
3246:
3243:
3241:
3238:
3237:
3235:
3231:
3225:
3222:
3220:
3217:
3215:
3212:
3210:
3207:
3205:
3202:
3200:
3197:
3196:
3194:
3190:
3184:
3181:
3179:
3176:
3174:
3171:
3169:
3166:
3164:
3161:
3159:
3156:
3154:
3151:
3149:
3146:
3145:
3143:
3139:
3135:
3128:
3123:
3121:
3116:
3114:
3109:
3108:
3105:
3092:
3086:
3082:
3081:
3075:
3073:
3068:
3062:
3058:
3053:
3049:
3043:
3039:
3038:
3032:
3031:
3013:
3009:
3003:
2995:
2991:
2987:
2981:
2977:
2970:
2964:
2960:
2957:
2951:
2942:
2934:
2928:
2920:
2916:
2912:
2906:
2902:
2895:
2886:
2884:
2874:
2865:
2856:
2854:
2852:
2842:
2833:
2824:
2815:
2813:
2803:
2796:
2791:
2782:
2780:
2767:
2763:
2757:
2748:
2746:
2736:
2734:
2719:
2718:
2711:
2707:
2698:
2695:
2693:
2690:
2688:
2685:
2684:
2663:
2656:
2641:
2634:
2619:
2612:
2597:
2590:
2589:
2588:
2574:
2565:
2548:
2544:
2537:
2533:
2529:
2520:
2516:
2510:
2507:
2499:
2481:
2474:
2459:
2452:
2437:
2430:
2415:
2408:
2393:
2386:
2365:
2357:
2342:
2335:
2334:
2333:
2312:
2308:
2303:
2294:
2285:
2281:
2277:
2274:
2265:
2262:
2255:
2254:
2253:
2251:
2241:
2238:
2235:
2232:
2229:
2228:
2224:
2221:
2218:
2215:
2212:
2211:
2207:
2204:
2201:
2198:
2195:
2194:
2190:
2187:
2184:
2181:
2178:
2177:
2173:
2170:
2167:
2164:
2161:
2160:
2153:
2150:
2147:
2146:
2131:Nut material
2129:
2121:Running speed
2113:
2110:
2107:
2106:
2102:
2099:
2096:
2095:
2091:
2088:
2085:
2084:
2080:
2077:
2074:
2073:
2052:
2043:
2023:
2014:
2011:
2010:
2004:
1988:
1985:
1982:
1979:
1973:
1967:
1964:
1961:
1956:
1953:
1950:
1947:
1941:
1935:
1932:
1929:
1923:
1920:
1912:
1909:
1889:
1862:
1836:
1826:
1816:
1812:
1806:
1797:
1785:
1781:
1780:
1779:
1759:
1748:
1733:
1709:
1702:
1698:
1695:
1691:
1687:
1684:
1681:
1678:
1675:
1669:
1665:
1662:
1659:
1655:
1651:
1648:
1645:
1639:
1633:
1623:
1619:
1613:
1609:
1602:
1598:
1595:
1592:
1589:
1586:
1577:
1573:
1568:
1565:
1561:
1557:
1554:
1545:
1541:
1538:
1532:
1526:
1516:
1512:
1506:
1497:
1489:
1474:
1467:
1463:
1460:
1456:
1452:
1449:
1446:
1443:
1440:
1434:
1430:
1427:
1424:
1420:
1416:
1413:
1410:
1404:
1398:
1388:
1384:
1378:
1374:
1367:
1363:
1360:
1357:
1354:
1351:
1342:
1338:
1332:
1328:
1325:
1316:
1312:
1309:
1306:
1303:
1297:
1291:
1281:
1277:
1271:
1262:
1254:
1253:
1252:
1225:
1221:
1218:
1215:
1211:
1206:
1203:
1197:
1193:
1190:
1184:
1172:
1168:
1165:
1160:
1157:
1151:
1140:
1134:
1130:
1124:
1110:
1109:
1108:
1100:
1098:
1082:
1079:
1076:
1049:
1041:Based on the
1023:
1016:
1014:
997:
990:
975:
968:
952:
945:
924:
916:
901:
894:
879:
872:
871:
870:
862:
859:
856:
853:
850:
849:
845:
842:
839:
836:
833:
832:
828:
825:
822:
819:
816:
815:
811:
808:
805:
802:
801:
798:Nut material
793:
771:
767:
764:
761:
757:
752:
749:
744:
734:
730:
724:
720:
714:
711:
708:
699:
695:
690:
687:
678:
674:
671:
665:
659:
649:
645:
639:
630:
622:
606:
602:
599:
596:
592:
587:
584:
579:
569:
565:
559:
555:
549:
546:
543:
534:
530:
519:
515:
512:
509:
506:
500:
494:
484:
480:
474:
465:
457:
456:
455:
453:
449:
426:
422:
408:
396:
393:
389:
386:
383:
379:
375:
372:
369:
365:
361:
358:
355:
354:roller screws
351:
348:
347:
346:
338:
336:
327:
324:
321:
318:
315:
312:
309:
306:
303:
300:
299:
298:
292:
291:Boeing 747-8F
287:
278:
273:
263:
261:
255:
248:An Acme screw
246:
237:
235:
231:
225:
218:Square thread
215:
213:
208:
198:
196:
186:
183:
178:
176:
172:
168:
164:
159:
157:
152:
150:
146:
142:
138:
137:machine tools
134:
130:
126:
122:
121:screw threads
118:
114:
113:linear motion
110:
106:
102:
98:
94:
90:
86:
77:
71:
70:stepper motor
66:
60:
59:square thread
55:
50:
44:
39:
33:
19:
3376:
3266:Differential
3261:Transmission
3214:Spiral bevel
3079:
3071:
3056:
3036:
3028:Bibliography
3015:. Retrieved
3011:
3002:
2975:
2969:
2950:
2941:
2900:
2894:
2873:
2864:
2841:
2832:
2823:
2802:
2790:
2756:
2721:, retrieved
2716:
2710:
2566:
2500:
2497:
2331:
2247:
2143:Speed (m/s)
2140:Speed (fpm)
1913:
1910:
1853:
1749:
1725:
1250:
1106:
1096:
1040:
1037:= lead angle
868:
448:horizontally
447:
413:
344:
341:Alternatives
331:
296:
275:
260:thread angle
257:
227:
204:
192:
179:
169:on a manual
160:
153:
123:have larger
96:
92:
88:
84:
82:
54:round thread
43:screw thread
3392:Chain drive
3352:Wheel train
3224:Herringbone
2795:Martin 2004
378:worm drives
360:Fluid power
350:Ball screws
304:Compactness
212:microlathes
182:hydrostatic
93:power screw
47:3 & 4:
3387:Belt drive
3372:Ball screw
3319:Derailleur
3153:Worm drive
3017:2020-08-26
2919:1076269063
2762:US 5499942
2723:2008-12-16
2703:References
2687:Ball screw
2222:20–40 fpm
2213:Cast iron
2205:20–40 fpm
2179:Cast iron
2157:Low speed
1120:efficiency
1103:Efficiency
1097:back-drive
863:0.06–0.09
846:0.11–0.17
829:0.15–0.25
817:Steel, dry
812:Cast iron
368:pneumatics
364:hydraulics
185:linkages.
125:frictional
103:used as a
89:lead screw
32:worm drive
18:Lead screw
3402:Freewheel
3382:Jackscrew
3377:Leadscrew
3254:Mechanics
2994:873995457
2927:cite book
2697:Jackscrew
2530:×
2278:×
2053:μ
2024:μ
2015:Starting
1989:λ
1986:
1980:μ
1968:α
1965:
1957:λ
1954:
1948:μ
1942:−
1936:α
1933:
1921:η
1863:μ
1817:μ
1734:α
1703:λ
1699:
1692:α
1688:
1682:μ
1670:λ
1666:
1660:−
1656:α
1652:
1646:μ
1603:α
1599:
1590:μ
1574:π
1566:−
1562:α
1558:
1542:μ
1539:π
1468:λ
1464:
1457:α
1453:
1447:μ
1444:−
1435:λ
1431:
1421:α
1417:
1411:μ
1368:α
1364:
1355:μ
1352:−
1339:π
1333:α
1329:
1313:μ
1310:π
1222:λ
1216:ϕ
1207:
1198:λ
1194:
1169:π
1083:λ
1077:ϕ
1024:λ
998:ϕ
953:μ
857:0.04–0.06
854:0.08–0.12
843:0.10–0.15
840:0.10–0.16
837:0.11–0.17
826:0.15–0.19
823:0.15–0.23
820:0.15–0.25
768:λ
765:−
762:ϕ
753:
712:μ
696:π
688:−
675:μ
672:π
603:λ
597:ϕ
588:
547:μ
544:−
531:π
516:μ
513:π
423:π
402:Mechanics
392:solenoids
335:split nut
230:efficient
163:split nut
119:members,
85:leadscrew
3422:Category
3365:See also
3344:Horology
3334:Sprocket
3324:Hub gear
3307:Bicycles
3300:Examples
3271:Coupling
3240:Involute
2959:Archived
2681:See also
2044:Running
892:= torque
234:friction
201:V-thread
129:actuator
3245:Cycloid
3219:Helical
3141:Systems
2239:50 fpm
2230:Bronze
2196:Bronze
2171:10 fpm
2162:Bronze
2148:Bronze
384:drives)
362:(i.e.,
145:presses
105:linkage
99:, is a
3428:Screws
3314:Cogset
3291:Offset
3192:Shapes
3087:
3063:
3044:
2992:
2982:
2917:
2907:
2771:
2332:where
2188:8 fpm
1977:
1971:
1945:
1939:
1854:where
1726:where
988:= lead
869:where
851:Bronze
806:Bronze
195:thread
147:, and
3276:Train
3209:Crown
3204:Bevel
3134:Gears
2114:0.06
2103:0.08
2092:0.09
2081:0.12
1502:lower
1267:raise
1177:raise
1145:raise
1054:lower
809:Brass
803:Steel
635:lower
470:raise
189:Types
171:lathe
149:jacks
141:vises
111:into
101:screw
3199:Spur
3085:ISBN
3061:ISBN
3042:ISBN
2990:OCLC
2980:ISBN
2933:link
2915:OCLC
2905:ISBN
2275:4.76
2111:0.08
2100:0.10
2089:0.15
2078:0.17
1080:>
374:Gear
366:and
352:and
207:Acme
175:wear
87:(or
1983:cot
1962:cos
1951:tan
1930:cos
1778:):
1696:tan
1685:sec
1663:tan
1649:sec
1596:sec
1555:sec
1461:tan
1450:sec
1428:tan
1414:sec
1361:sec
1326:sec
1204:tan
1191:tan
750:tan
585:tan
139:),
95:or
57:6:
52:5:
3424::
3070:.
3010:.
2988:.
2929:}}
2925:{{
2913:.
2882:^
2850:^
2811:^
2778:^
2744:^
2732:^
2534:10
2282:10
1011:=
380:,
197:.
180:A
158:.
143:,
83:A
3126:e
3119:t
3112:v
3094:.
3051:.
3020:.
2996:.
2935:)
2921:.
2727:.
2664:C
2642:C
2620:C
2598:C
2575:C
2549:2
2545:L
2538:7
2525:r
2521:d
2517:C
2511:=
2508:N
2482:C
2460:C
2438:C
2416:C
2394:L
2370:r
2366:d
2343:N
2313:2
2309:L
2304:C
2299:r
2295:d
2291:)
2286:6
2272:(
2266:=
2263:N
2057:c
2028:c
1974:+
1924:=
1894:c
1890:d
1867:c
1837:2
1831:c
1827:d
1821:c
1813:F
1807:=
1802:c
1798:T
1764:c
1760:d
1751:(
1710:)
1679:+
1676:1
1640:(
1634:2
1628:m
1624:d
1620:F
1614:=
1610:)
1593:l
1587:+
1582:m
1578:d
1569:l
1550:m
1546:d
1533:(
1527:2
1521:m
1517:d
1513:F
1507:=
1498:T
1475:)
1441:1
1425:+
1405:(
1399:2
1393:m
1389:d
1385:F
1379:=
1375:)
1358:l
1347:m
1343:d
1321:m
1317:d
1307:+
1304:l
1298:(
1292:2
1286:m
1282:d
1278:F
1272:=
1263:T
1226:)
1219:+
1212:(
1185:=
1173:T
1166:2
1161:l
1158:F
1152:=
1141:T
1135:0
1131:T
1125:=
1069:(
1050:T
976:l
929:m
925:d
902:F
880:T
860:-
772:)
758:(
745:2
739:m
735:d
731:F
725:=
721:)
715:l
709:+
704:m
700:d
691:l
683:m
679:d
666:(
660:2
654:m
650:d
646:F
640:=
631:T
607:)
600:+
593:(
580:2
574:m
570:d
566:F
560:=
556:)
550:l
539:m
535:d
524:m
520:d
510:+
507:l
501:(
495:2
489:m
485:d
481:F
475:=
466:T
431:m
427:d
394:)
370:)
34:.
20:)
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