Function, Construction and Operation - PowerPoint Presentation

Slide1

Function, Construction and Operation

DRIVE SHAFTSlide2

Drive Shaft

Function

-to transmit power from one point to another in a smooth, constinuos action.-In trucks and construction equipment,the drive shaft is designed to send torque through an angle from the transmission to the axle( or auxiliaryt ransmission).

-The

drive shaft must operate through constantly

changing

relative angles

the between transmission

and axle

.

- it must

also be capable of changing length while transmitting

torque

.

- The

axle of a vehicle is not attached directly

to

the frame, but rides suspended by springs in an irregular,

floating

motion. Slide3
Slide4

Construction of

a

Drive Shaft-To transmit required torque loads, the drive shaft must be durable and strong. Forged steel and high-strengrth, cast, end yoke for heavy-duty vehicles are used to provide the necessary rigidity required to maintain bearing alignment under torque loads.

-Anti-friction bearings are

used to

with stand oscillating

loads while the drive shaft is rotating at high speeds. The needle roller bearings on the cross trunnions carry large loads and are used because of their high capacity in a limited space.

-Abrasive

material is a major problem for vehicles operating

in extremely moist and

dirty

environments.

T

o

Combat

this problem, synthetic rubber seals were developed

and

resulted in increased life, ability to

with stand

high temperatures and

a less

critical

relubrication

cycle

for

drive shafts.Slide5

-Special high-strength tubing

is used to

provide maximum torque carrying capacrty at minimum practical weight. Drive shafts have been developed to meet the vehicular industry needs.-The slidings plines betweens

lip joint and

permanent joint

must

support the drive shaft and be capable of sliding under full torque loads. -To aid in this axial or slip movement, Glidecote was developed to reduce sliding friction, reducing thrust under

hight

orque.This

non-

metalli

coating

also

prevents spline galling and extends spline life.Slide6
Slide7
Slide8

Operation of Drive Shaft

-Each

shaft is installed in the same manner. A universal joint (Cardan type) and splined slip yoke are located at the transmission end of the shaft, where they are held in alignment by a bushing in the transmission rear extension. -The slip yoke permits fore and aft movement of the driveshaft as the differential assembly moves up and down. The spline is lubricated internally by transmission lubrication or grease. An oil seal at the transmission prevents leakage and protects the slip yoke from dust, dirt and other harmful material .

-From

some automatic transmissions, the slip yoke spline is lubricated with grease

and

provided with a small vent hole. The slip yokes should be inspected to be sure the vent hole is clear (Figure 19).Slide9

DRIVE SHAFT SERVICESlide10

I

NSPECTING END FITTINGS

Visually inspect all input and output end-fitting (yoke) retaining nuts, clips, or bolts for any gaps between mating surfaces. If gaps are present, consult transmission, axle or transfer case original equipment manufacturers’ service and maintenance manuals for proper fastener specifications. Try to move it vertically and horizontally to feel any looseness. (See photo left.) Listen for any clicking, or grinding noise from the

joint.

Take hold of the end fitting with both hands, rotate left to right, feeling for play or backlash (see photo left.) Listen for any clicking, or grinding noise from the joint. If radial looseness is evident, U-joints or yokes will have to be

replaced.Slide11

. (See photo left above.) There should be less than .006 in. (.15mm) movement in the universal joint kit relative to the inboard or outboard yokes. If looseness is greater than .006 in. (.15mm), the universal joint kit must be replaced.

I

NSPECTING UNIVERSAL JOINTS

Type

1.Relubable

style

2.Permanently Lubricated Plug Style3.Permanently Lubricated Net-Formed StyleSlide12

Reubable

style

Check for the presence of all grease zerk (nipple) fittings. (See photo left). Grease zerk (nipple) fittings should not be missing, loose or fractured.

Permanently Lubricated Plug

Style

Permanently lubricated plug style universal joint kits do not contain grease

zerk fittings, only a plug. (See photo left) Make sure plug is not missing, loose or fractured. If the plug is loose, tighten to required specifications.

Permanently Lubricated Net-Formed Style

Net-formed universal joints do not contain grease

zerk

(nipple) fittings or plugs and are not

relubable

(See photo left

).Slide13

INSPECTING SLIP MEMBERS

Check the slip member assembly for excessive radial looseness.

(See photo left) If looseness is greater than .012 in. (.30mm) as read on dial indicator, replacement of the slip member assembly is necessary.

For an inboard and outboard slip yoke assembly design, check to be sure the slip yoke welch plug is not loose, missing or damaged. (See photo left) If any of these situations are evident, replacement of the slip yoke and professional

are

balancing of the driveshaft is necessary.

Visually inspect for the presence of the grease

zerk

fitting, if applicable, on the slip yoke. (See photo left) Grease

zerk

fittings should not be missing, loose or

fractured.Slide14

Check the slip yoke seal. (See photo left) Make sure the seal is properly attached to the slip yoke and is not loose or damaged. If any of these situations are evident, replacement of slip member assembly is necessary.

For permanently lubricated slip members, check yoke shaft boot (see photo left) or seal can. Make sure the boot or seal can is properly attached to the yoke shaft and tube sleeve and no damage or looseness is apparent

INSPECTING

TUBING

Check the driveshaft for bent or dented tubing, cracks, or failed welds. If any of these situations is evident, replacement of the complete driveshaft assembly or tube is necessary.Slide15

INSPECTING CENTER BEARINGS

Visually inspect all

center bearings, end-fitting midship nuts for any gaps between the mating surfaces. (See photo left) Be sure to repeat check for broken back and backlash.for all center bearing end fittings.

Inspect the

center

bearing bracket bolts for looseness. (See photo left) If looseness is evident,

are tighten

center

bearing bracket

bolts.

Check the alignment of the bracket before tightening the

bolts.

If any of these situations are evident, replacement of the

center

bearing assembly is necessary.Slide16

THE END