20:
119:
201:). Early PTOs were often taken off the main output shaft, meaning that the vehicle had to be "in gear" in order to run the PTO. Later this was improved by so-called live PTO (LPTO) designs, which allow control of the PTO rotation independently of the tractor motion. This is an advantage when the load driven by the PTO requires the tractor motion to slow or stop running to allow the PTO driven equipment to catch up. It also allows operations where the tractor remains parked, such as silo-filling or unloading a
222:
31:
516:
508:
531:
transmission. Care is also needed to ensure that the physical space around the transmission allows for installation of the PTO. The PTO is engaged and disengaged using the main transmission clutch and a remote control mechanism which operates on the PTO itself. Typically, an air valve is used to engage the PTO, but a mechanical linkage, electric or hydraulic mechanism are also options.
480:. A six-spline adapter was usually supplied. It is customary for agricultural machines manufacturers to provide the nominal PTO power specification, an indication of the available instantaneous power at the shaft. Newer tractors may come equipped with 540/540E and/or 1000/1000E options that allow the tractor to power certain low-power-demand implements like
457:
Due to ever-increasing horsepower requirements from farm implements, and higher horsepower engines being installed in farm tractors, a still larger type (designated as Type 4) has been added to ISO 500. It operates at a higher rotational speed of 1300 rpm in order to allow for power transfer at
327:
Two newer types, supporting higher power applications, operate at 1000 rpm and differ in shaft size. Farmers typically differentiate these two types by calling them "large 1000" or "small 1000" as compared to the Type 1 which is commonly referred to as the "540". All new types (2, 3, and 4) use
177:
Company (IHC) was first to market with a PTO on a production tractor, with its model 8-16, introduced in 1918. Edward A. Johnston, an IHC engineer, had been impressed by a homemade PTO that he saw in France about a decade before, improvised by a French farmer and mechanic surnamed Gougis. He and his
630:
A "sandwich" type split shaft unit is mounted between engine and transmission and used on road maintenance vehicles, fire fighting vehicles and off-road vehicles. This unit gets the drive directly from the engine shaft and can be capable of delivering up to the complete engine power to the PTO.
213:, Ontario, Canada, introduced the Cockshutt Model 30 tractor with LPTO. Live PTOs eventually became a widespread norm for new equipment; in modern tractors, LPTO is often controlled by push-button or selector switch. This increases safety of operators who need to get close to the PTO shaft.
530:
have one or more locations which allow for a PTO to be mounted. The PTO must be purchased separately and care is required to match the physical interface of the transmission with a compatible PTO. PTO suppliers will usually require details of the make, model and even serial number of the
256:; "He appeared to have been working on his truck when his clothes became tangled in the truck's power take-off shaft", District Attorney Joseph Early Jr. said in a statement. Despite much work to reduce the frequency and severity of agricultural injuries, these events still occur.
178:
IHC colleagues incorporated the idea into the 8-16, and designed a family of implements to take advantage of the feature. IHC was not alone in the market for long, as within a year PTOs were appearing on other production tractors, such as some
607:
The unit itself is designed to independently divert the engine's power to either the axle-facing shaft or the additional PTO output shaft. This is done by two independent clutches like tooth or dog clutches, which can be operated at total
102:. Jet aircraft have four types of PTO units: internal gearbox, external gearbox, radial drive shaft, and bleed air, which are used to power engine accessories. In some cases, aircraft power take-off systems also provide for putting power
714:
The medal for the first recorded power take-off on a piece of mobile machinery on the other hand ought to go to an
Aveling and Porter Bell-type reaper. This steam-powered outfit was put on show at the 1878 Universal Exposition in
669:
NASA Technical
Memorandum 101731; Monitoring Techniques for "X-29A Aircraft's High Speed Rotating Power Takeoff Shaft"; David F Voracek, Ames Research Center, Dryden Flight Research Facility, Edwards, California, December 1990
170:. The concept of a shaft drive with easily connected and disconnected couplings, and flexibility for driving at changing angles (such as when an articulated tractor-and-trailer combination turns), was a goal to pursue.
631:
Usually these units come with their own lubricating system. Due to the sandwich mounting style, the gearbox will be moved away from the engine, requiring the driveline to accommodate the installation.
134:
Various power transmission methods were available before power take-offs became common, but there were applications which would benefit more from some of the attributes that PTOs would provide.
541:
Units will be rated according to the continuous and intermittent torque that can be applied through them and different models will offer different "PTO shaft rotation to engine RPM" ratios.
473:
All four types rotate counterclockwise when viewed looking back from inside the tractor's cab; when standing behind the tractor and looking directly at the shaft, it turns clockwise.
596:
A split shaft PTO is mounted to the truck's drive shaft to provide power to the PTO. Such a unit is an additional gearbox that separates the vehicle's drive shaft into two parts:
488:
using lower engine speeds to maintain the revolutions per minute needed, using less fuel and placing less stress on the engine – thereby improving efficiency and reducing costs.
237:, six percent of tractor related fatalities in 1997 in the United States involved the PTO. Incidents can occur when loose clothing is pulled into the shaft, often resulting in
166:'s crank, for example), but such a transmission ceases if the vehicle stops traveling, and the workload's resistance tends to make the wheel skid rather than turn, even if
162:, the implement could receive rotary power by taking it from one of its own wheels (whose turning was imparted by the towing) and distributing it via roller chains (to a
496:
825:
552:
system to any location around the vehicle where a hydraulic motor will convert it back into rotary or linear mechanical force. Typical applications include:
499:) in April 1927. The PTO rotational speed was specified as 536 ± 10 rpm; the direction was clockwise. The speed was later changed to 540 rpm.
995:
612:
standstill only. Because the main gearbox changes the rotation speed by selection of a gear, the PTO cannot be operated while the vehicle is moving.
259:
Some implements employ light free-spinning protective plastic guards to enshroud the PTO shaft; these are mandatory in some countries. In the UK,
684:
83:
Semi-permanently mounted power take-offs can also be found on industrial and marine engines. These applications typically use a drive shaft and
276:
87:
to transmit power to a secondary implement or accessory. In the case of a marine application, such as shafts may be used to power fire pumps.
173:
Experimental power take-offs were tried as early as 1878, and various homemade versions were constructed over the subsequent decades.
615:
On 4x4 vehicles, only the rear drive shaft is used by the split shaft PTO gearbox, requiring the vehicle's 4x4 drive scheme to be of the
1026:
182:
models. In 1920, IHC offered the PTO option on their 15-30 tractor, and it was the first PTO-equipped tractor to be submitted for a
932:
559:
Running a truck mounted hot water extraction machine for carpet cleaning (driving vacuum blower and high-pressure solution pumps)
967:
186:. The PTO was a competitive advantage for IHC in the 1920s, and other companies eventually caught up with PTO implementation.
1077:
622:
It is also possible to connect something other than a hydraulic pump directly to the PTO: for example, fire truck pumps.
902:
571:
Operating the mechanical arm on a bucket truck used by electrical maintenance personnel or cable TV maintenance crews
832:
857:
981:
1101:
159:
1002:
897:
260:
19:
59:
699:
335:
Inch-denominated shafts are round, rectangular, square, or splined; metric shafts are star, bell, or
197:
where the power is taken off determines whether the PTO can be run independently of vehicle travel (
190:
234:
174:
127:
135:
1096:
640:
307:
206:
890:"Agriculture Information Sheet No 40 (AIS40). Power take-offs and power take-off drive shafts"
671:
246:
138:
were generally only useful for applications where the engine was stationary, such as factory
118:
968:"Equipment Hub: Understanding power takeoff drivelines - Progressive Forage | Ag Proud"
600:
The gearbox-facing shaft which will transmit the power of the engine to the split shaft PTO;
290:
General specifications, safety requirements, dimensions for master shield and clearance zone
99:
8:
527:
66:
183:
861:
802:
769:
492:
233:, are a common cause of incidents and injury in farming and industry. According to the
538:
come with front and/or rear PTOs and hydraulics as well as three point hitch systems.
1073:
1020:
807:
789:
650:
336:
35:
54:) is one of several methods for taking power from a power source, such as a running
797:
781:
619:
type to keep the front axle drive shaft completely decoupled during PTO operation.
485:
179:
785:
245:, other permanent disabilities, or death to its wearer. On April 13, 2009, former
742:
549:
458:
reduced levels of torque. The shaft has 22 splines with a major diameter of 57.5
272:
253:
230:
202:
151:
147:
143:
107:
95:
770:"Marketing Farm Safety: Using Principles of Influence to Increase PTO Shielding"
310:(rpm). A shaft that rotates at 540 rpm has six splines on it, and a diameter of
545:
80:
allowing implements with mating fittings to be powered directly by the engine.
877:
shields and guards were developed to prevent injury from these rotating shafts
1090:
1070:
Farmall
Tractors: History of International McCormick-Deering Farmall Tractors
793:
238:
811:
250:
198:
139:
84:
163:
933:"Agricultural tractors - Rear-mounted power take-off types 1, 2, 3 and 4"
889:
459:
123:
69:
865:
62:
it to an application such as an attached implement or separate machine.
1040:
584:
477:
467:
242:
221:
194:
603:
The axle-facing shaft which transmit the propelling power to the axle.
296:
Narrow-track tractors, dimensions for master shield and clearance zone
609:
476:
A 10-spline type was used with some early equipment such as the 1948
463:
210:
30:
306:
The original type (designated as Type 1) calls for operation at 540
1041:"PTO Air Compressors | Direct-Transmission™ Mounted Air Compressor"
481:
329:
91:
562:
Powering a blower system used to move dry materials such as cement
645:
515:
167:
155:
73:
24:
548:. This allows for transmission of mechanical force through the
535:
520:
55:
519:
Rear crossbar with PTO hydraulic connectors and coupling on a
507:
16:
Methods for transmitting power from a source to an application
544:
In the majority of cases, the PTO will connect directly to a
77:
1072:, Farm Tractor Color History Series, Osceola, WI, USA: MBI,
302:
Main PTO dimensions and spline dimensions, location of PTO.
283:, which as of the 2004 edition was split into three parts:
150:
parked in front of the work. For moving vehicles such as a
1068:
Pripps, Robert N.; Morland, Andrew (photographer) (1993),
725:
723:
860:. Department of Agricultural and Biological Engineering.
685:"Spinning an historical yarn about power-take-off shafts"
205:
to a pile or lagoon rather than across a field. In 1945,
720:
930:
34:
A PTO (in the box at the bottom) in the center of the
556:
Running a water pump on a fire engine or water truck
831:. National Safety Council. May 2009. Archived from
625:
565:
Powering a vehicle-integrated air compressor system
768:Tinc, Pamela J.; Sorensen, Julie A. (2019-01-02).
462:(mm). It is meant to handle PTO powers up to 450
225:Protective plastic sheath enshrouding a PTO shaft
1088:
332:splines, whereas Type 1 uses straight splines.
229:The PTO, as well as its associated shafts and
1067:
729:
502:
767:
698:(6). Greenmount Press: 36–37. Archived from
266:
735:
962:
960:
958:
956:
577:Operating the compactor on a garbage truck
511:A hydraulic PTO mounted on a truck gearbox
497:American Society of Agricultural Engineers
254:died as a result of a PTO related accident
801:
106:the engine during engine start. See also
931:International Standard (April 1, 2014).
855:
514:
506:
495:for PTO design was adopted by ASAE (the
220:
117:
29:
18:
953:
858:"Farm Safety & Health - PTO Safety"
849:
743:"Examiner: Fidrych suffocated to death"
676:
1089:
1025:: CS1 maint: archived copy as title (
974:
926:
924:
922:
682:
663:
122:Yellow shaft provides PTO drive to a
882:
263:guidance is contained in a leaflet.
982:"The Different Types of PTO Shafts"
13:
919:
818:
683:Quick, Graeme (March–April 2008).
98:may be used in conjunction with a
14:
1113:
856:Privette, Charles (2002-03-01).
574:Operating a winch on a tow truck
446:57.5 millimetres (2.26 in)
23:A PTO at the rear end of a farm
1061:
1033:
988:
908:from the original on 2021-10-31
898:Health and Safety Executive UK
761:
591:
580:Operating a Boom/Grapple truck
1:
826:"Power-Take-Off (PTO) Safety"
786:10.1080/1059924X.2018.1539421
656:
275:in dimensions and speed. The
207:Cockshutt Farm Equipment Ltd
193:, the exact point along the
7:
634:
261:Health and Safety Executive
144:portable stationary engines
10:
1118:
583:Operating a truck mounted
503:Use on commercial vehicles
113:
730:Pripps & Morland 1993
267:Technical standardization
216:
568:Raising a dump truck bed
774:Journal of Agromedicine
432: in or 44 mm
405: in or 35 mm
378: in or 35 mm
235:National Safety Council
175:International Harvester
128:International Harvester
65:Most commonly, it is a
1102:Agricultural machinery
940:International Standard
641:Agricultural machinery
626:"Sandwich" split shaft
587:and lift-mast assembly
524:
512:
308:revolutions per minute
271:Agricultural PTOs are
226:
131:
94:applications, such an
39:
27:
518:
510:
466:(kW), or roughly 600
324:inches (35 mm).
279:standard for PTOs is
247:Major League Baseball
224:
184:Nebraska tractor test
121:
33:
22:
100:constant speed drive
984:. 15 February 2021.
528:Truck transmissions
491:The first industry
862:Clemson University
525:
513:
227:
132:
40:
28:
1079:978-0-87938-763-1
901:. October 2013 .
732:, pp. 37–39.
651:Two-wheel tractor
453:
452:
36:three-point hitch
1109:
1083:
1055:
1054:
1052:
1051:
1037:
1031:
1030:
1024:
1016:
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1013:
1007:
1001:. Archived from
1000:
992:
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978:
972:
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937:
928:
917:
916:
914:
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886:
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879:
874:
873:
864:. Archived from
853:
847:
846:
844:
843:
837:
830:
822:
816:
815:
805:
765:
759:
758:
756:
754:
739:
733:
727:
718:
717:
711:
710:
704:
692:Australian Grain
689:
680:
674:
667:
431:
430:
426:
423:
404:
403:
399:
396:
377:
376:
372:
369:
342:
341:
323:
322:
318:
315:
231:universal joints
148:traction engines
1117:
1116:
1112:
1111:
1110:
1108:
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1106:
1087:
1086:
1080:
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1058:
1049:
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1011:
1009:
1005:
998:
996:"Archived copy"
994:
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979:
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966:
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935:
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839:
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824:
823:
819:
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749:. 16 April 2009
741:
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728:
721:
708:
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664:
659:
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628:
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550:hydraulic fluid
505:
428:
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421:
419:
401:
397:
394:
392:
374:
370:
367:
365:
320:
316:
313:
311:
269:
219:
203:manure spreader
152:traction engine
116:
108:Coffman starter
96:accessory drive
72:installed on a
17:
12:
11:
5:
1115:
1105:
1104:
1099:
1085:
1084:
1078:
1063:
1060:
1057:
1056:
1032:
987:
973:
952:
918:
881:
848:
817:
780:(1): 101–109.
760:
734:
719:
675:
661:
660:
658:
655:
654:
653:
648:
643:
636:
633:
627:
624:
617:selectable 4WD
605:
604:
601:
593:
590:
589:
588:
581:
578:
575:
572:
569:
566:
563:
560:
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546:hydraulic pump
504:
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297:
291:
268:
265:
239:bone fractures
218:
215:
160:farm implement
115:
112:
44:power take-off
15:
9:
6:
4:
3:
2:
1114:
1103:
1100:
1098:
1097:ISO standards
1095:
1094:
1092:
1081:
1075:
1071:
1066:
1065:
1046:
1042:
1036:
1028:
1022:
1008:on 2011-07-22
1004:
997:
991:
983:
977:
969:
963:
961:
959:
957:
945:September 29,
941:
934:
927:
925:
923:
904:
900:
899:
891:
885:
878:
868:on 2005-03-28
867:
863:
859:
852:
838:on 2014-04-28
834:
827:
821:
813:
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799:
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764:
748:
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738:
731:
726:
724:
716:
705:on 2021-02-26
701:
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289:
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264:
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257:
255:
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244:
243:loss of limbs
240:
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223:
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208:
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200:
196:
192:
187:
185:
181:
176:
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149:
145:
141:
140:steam engines
137:
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125:
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111:
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105:
101:
97:
93:
88:
86:
81:
79:
75:
71:
68:
63:
61:
57:
53:
49:
48:power takeoff
45:
37:
32:
26:
21:
1069:
1062:Bibliography
1048:. Retrieved
1044:
1035:
1010:. Retrieved
1003:the original
990:
976:
943:. Retrieved
939:
910:. Retrieved
896:
884:
876:
870:. Retrieved
866:the original
851:
840:. Retrieved
833:the original
820:
777:
773:
763:
751:. Retrieved
746:
737:
713:
707:. Retrieved
700:the original
695:
691:
678:
665:
629:
621:
616:
614:
606:
595:
543:
540:
533:
526:
490:
475:
472:
456:
454:
449:22 involute
435:20 involute
408:21 involute
334:
326:
305:
299:
293:
287:
280:
273:standardized
270:
258:
251:Mark Fidrych
228:
199:ground speed
191:transmission
188:
172:
133:
103:
89:
85:bolted joint
82:
64:
60:transmitting
51:
47:
43:
41:
38:of a tractor
592:Split shaft
460:millimeters
381:6 straight
189:Inside the
124:flail mower
70:drive shaft
1091:Categories
1050:2018-12-11
1012:2009-05-03
912:2022-07-29
872:2022-07-29
842:2022-07-28
709:2022-07-28
657:References
585:tree spade
478:Land Rover
468:horsepower
195:gear train
164:sickle bar
136:Flat belts
794:1059-924X
753:7 January
610:driveline
482:hay rakes
464:kilowatts
351:Diameter
339:-shaped.
300:ISO 500-3
294:ISO 500-2
288:ISO 500-1
211:Brantford
158:towing a
154:or early
1021:cite web
903:Archived
812:30346257
747:ESPN.com
672:nasa.gov
635:See also
493:standard
354:Splines
337:football
330:involute
126:on this
92:aircraft
803:6353692
646:Tractor
536:Unimogs
486:tedders
427:⁄
400:⁄
373:⁄
319:⁄
281:ISO 500
168:cleated
156:tractor
130:tractor
114:History
74:tractor
67:splined
25:tractor
1076:
810:
800:
792:
715:Paris.
521:Unimog
470:(hp).
443:1,300
416:1,000
389:1,000
217:Safety
58:, and
56:engine
1006:(PDF)
999:(PDF)
936:(PDF)
906:(PDF)
893:(PDF)
836:(PDF)
829:(PDF)
703:(PDF)
688:(PDF)
534:Most
345:Type
249:star
146:, or
78:truck
1074:ISBN
1045:VMAC
1027:link
947:2023
808:PMID
790:ISSN
755:2014
362:540
348:RPM
180:Case
104:into
798:PMC
782:doi
523:421
484:or
277:ISO
209:of
90:In
76:or
52:PTO
46:or
1093::
1043:.
1023:}}
1019:{{
955:^
938:.
921:^
895:.
875:.
806:.
796:.
788:.
778:24
776:.
772:.
745:.
722:^
712:.
696:17
694:.
690:.
440:4
413:3
386:2
359:1
241:,
142:,
110:.
42:A
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1053:.
1029:)
1015:.
970:.
949:.
915:.
845:.
814:.
784::
757:.
429:4
425:3
422:+
420:1
402:8
398:3
395:+
393:1
375:8
371:3
368:+
366:1
321:8
317:3
314:+
312:1
50:(
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