What is drive shaft , driveshaft , driving shaft , propeller shaft

What is drive shaft , driveshaft , driving shaft , propeller shaft

A drive shaft, driveshaft, driving shaft, propeller shaft (prop shaft), or Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement between them.

As torque carriers, drive shafts are subject to torsion and shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, while avoiding too much additional weight as that would in turn increase their inertia.

To allow for variations in the alignment and distance between the driving and driven components, drive shafts frequently incorporate one or more universal joints, jaw couplings, or rag joints, and sometimes a splined joint or prismatic joint.

The propeller shaft is a shaft that transmits power from transmission (gear box) to the differential. On one end, propeller shaft in connected to main transmission shaft by universal joint. On the other hand, it is connected to differential pinion shaft by another universal joint. Propeller shaft transmits the rotary motion of main transmission shaft (coming from gear box) to the differential so that rear wheels can be rotated. A sliding (slip) joint, is also fitted between universal joint and propeller shaft on transmission side which takes care of axial motion of propeller shaft. Propeller shaft is made of a steel tube which can withstand torsional stresses and vibrations at high speeds.
It is important to note that the differential pinion shaft and transmission main shaft are not in single horizontal level. The rear axle and differential is attached to automobile frame via springs. Therefore, distance between differential and gear box keeps on changing as vehicle moves along irregular road surface. Angle of propeller shaft also changes due to this fact. Universal joints provided at two ends takes care of these two changes. The propeller shaft along with universal joints has been shown in Figure

Propeller Shaft Figure :

Drive shaft parts :

What are the functions of a propeller shaft ?

The main function of propeller shaft is to connect two mechanical elements or component i.e. one is driving element and another is driven element. We can transmit torque/turning moment and power from one component to another which are apart at some distance. Propeller shaft in vehicle and ship just connects the main engine to the power drive which drives the vehicle or ship.

The main failure which is generally observed in propeller shaft is twisting moment due to excessive shear stress. By proper designing of shaft we can overcome this failure.

Types of Propeller Shaft:

Single-Piece-Type Propeller Shaft:
Used in vehicles with a short distance between the engine and axles, and MR based four-wheel-drive vehicles.

The friction welding
adopted at the junction contributes to an improvement in the strength, quality, and durability of the junction.

2. 2-piece-type/3-piece-type Propeller Shaft:
Utilized as a part of vehicles with a long distance between the engine and axles, and Front engine front drive base four-wheel-drive vehicles.
The division of the propeller shaft into two- or three-parts allows the critical number of revolution to lowered preventing vibration issue from occurring, when the overall length of the shaft increased.