动力输出轴--文献翻译

3.0 闻远设计 2023-09-29 79 4 82KB 14 页 15光币

侵权投诉

车辆与动力工程学院毕业设计说明书

Power takeoff shaft

The power takeoff shaft usually called simply the power

takeoff ,provides a means to drive the machine that are being towed

by the tractor .the engine power of the tractor is being used not

only to pull or carry the machine ,but also to operate it .typical

exampled of machines that are power driven are

mowers .,balers ,combine.potato harvests ,and manure spreader .the

P T O p r o v i d e s a v e r y u s e f u l s o u r c e o f p o w e r . a n d t h e a l t e r n a t i v e

would be to fit an engine to each of these machine .this is ,of

course done where the power required to drive the machine may be

greater than the tractor can be supply. Generally most machines can

be powered by the tractor .

Power take off shaft are calssifily according to their location

of the tractor,type of the drive .rotation speed ,and method of

control .

Most tractor are equipped with a rear PTO.some of them have a

front PTO ,ROW-tractor use both a rear and a side PTO .

A S t o t h e t y p e o f d r i v e , p o w e r t a k e o f f s h a f t a r e c l a s s e d a s

transmission drive .live ,semi-independent ,and ground-speed

t y p e , t h e t r a n s m i s s i o n d r i v e P T O I S d r i v e n f r o m t h e t r a c t o r

transmission and so it will stop rotating whenever the engine

clutch is disengage .

T h e l i v e P T O i s d r i v e n f r o m t h e e n g i n e c r a n k s h a f t t h r o u g h t h e

clutch driving member irrespective of the position of the clutch

.the semi-independent PTO WILL continue to operate while the driver

is shifting gears , but is incapable of being engaged or disengaged

w h i l e t h e t r a c t o r i s m o v i n g . t h e g r o u n d - s p e e d P T O h a s i t s s p e e d

proportional to the ground speed of the tractor .such A PTO finds

application on row-crop tractors to operate machine .such as

mounted drills .whose working rate must be in synchronism with the

车辆与动力工程学院毕业设计说明书

ground speed of the tractor .

The power takeoff are standardized at 540 and 1000rpm (AT nominal

engine speed )the spined ends of PTO shaft of all tractor are of

one and same size and are arranged at one and the same level

relative to the tractor support surface .when the PTO Shaft is not

used ,its end is covered by a guard stamped from sheet steel.

Power takeoff shaft may be control by either mechanical or

hydraulic means

Live PTO shaft can be engage or disengage on the run by hydraulic

or complex mechanical means.

When the PTO is disengage , sun gear brake is released and planet

carrier is applied. In this case ,PTO shaft is held stationary and

the planet gear transmit rotation from the internal gear to the sun

gear .

W h e n t h e P T O i s e n g a g e d . s u n g e a r b r a k e i s a p p l i e d a n d p l a n e t

carrier is released. The planet gears now have to walk around the

sun gear .as the planet gears roll around the sun gear.they carry

t h e p l a n e t c a r r i e r a r o u n d w i t h t h e m . t h u s d r i v i n g t h e P T O s h a f t

which is rigidly connected the planer carrier.

When the PTO is not used the PTO control lever is placed into its

neutral (central) position. In this case.both the sun gear and the

planet carrier brakes are released.

T o o t h e d c l u t c h 1 i n s e r t e d i n t o t h e P T O d r i v i n g l i n e m a k e s i t

possible to have either independent or ground-speed power takeoff.

The clutch is operated by a control lever and can be placed into

three different positions. When the clutch is shifted all the way

forward (to the left .as shown in Fig.165a), drive shaft 9(see

Fig.164) of the PTO nit is connected to the transmission

main(output) shaft to obtain ground-speed power takeoff. If the

clutch is moved all the way backward (to the right .as shown in

Fig.165b). the drive shaft of the PTO unit will be connected to the

车辆与动力工程学院毕业设计说明书

engine crankshaft, and so power takeoff will be independent. With

t h e c l u t c h i n i t s n e u t r a l ( c e n t r a l ) p o s i t i o n . n o d r i v e i s

transmitted to the PTO unit.

To place the clutch into the “GROUND-SPEED PTO”position, one

should disengage the engine clutch, whereas placing it into the

“LIVE PTO”position required that the engine should be stopped.

THE HYDRAULICALLY CONTROLLED PTO UNIT (Fig.166) includes a

planetary gear set and a self-contained hydraulic system. The unit

is contained in a case that is attached to the rear axle housing of

the tractor.

T h e r e d u c t i o n g e a r s e t o f t h e P T O u n i t c o m p r i s e s d r i v e g e a r 3

carried on shaft 1 and driven gear 9 and hydraulic clutch 10 that

are mounted on PTO shaft 5. The shafts are supported by ball

bearings housed in bores in the PTO case. Drive gear shaft 1 is

driven from the engine crankshaft, and so the unit provides splined

to its shaft and is in constant mesh with a hub that is freely

supported by ball bearings on the PTO shaft.

T h e c o n n e c t i o n b e t w e e n t h e d r i v e n g e a r a n d t h e P T O s h a f t i s

effected by hydraulic clutch 10 similar to those described in

Section 11.4. The clutch comprises a series of driving and driven

discs accommodated in a drum that is splined to the PTO shaft. The

c l u t c h d r i v i n g d i s c s a r e m a d e o f s t e e l a n d e q u i p p e d w i t h c e r m e t

l i n i n g s . T h e s e d i s c s a r e s p l i n e d o n t o t h e d r i v e g e a r h u b . T h e

clutch driven discs of plain steel are arranged alternately between

the driving discs and are splined into the clutch drum. Inside the

clutch drum, there is annular space 12 that plays the part of a

hydraulic cylinder, into which fits piston 11. The piston is sealed

in the annular space of the clutch drum by a cast-iron ring on the

outside and a rubber ring on the inside and is loaded by a series

of springs 14.

To engage the clutch and hence the PTO shaft, oil is delivered

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

15 光币 4人已下载

立即下载

标签： #翻译 #动力输出

摘要：

车辆与动力工程学院毕业设计说明书PowertakeoffshaftThepowertakeoffshaftusuallycalledsimplythepowertakeoff,providesameanstodrivethemachinethatarebeingtowedbythetractor.theenginepowerofthetractorisbeingusednotonlytopullorcarrythemachine,butalsotooperateit.typicalexampledofmachinesthatarepowerdrivenaremowers.,balers,com...

展开>> 收起<<

动力输出轴--文献翻译.doc

共14页,预览5页

还剩页未读，继续阅读

动力输出轴--文献翻译

相关推荐

开通VIP享超值会员特权

作者详情

相关内容

推荐作者

热门标签

举报选择: