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2019.10.25 update

How does the PTO works?

Have you ever heard about PTO (Power Take Off)? Truck have various functions depending on its application. For example, dump trucks tilt the loading platforms to unload cargo, and mixer trucks rotate drums to prevent cement from being set. In addition, many garbage trucks have function that compress garbage automatically. PTO is used to convert the energy from the engine to those truck bodies in order to perform such operations.

PTO (Power Take Off) is one of the functions for the active use of the truck. PTO is mainly mounted on work vehicles such as dump trucks and mixer trucks. A power source is required for the truck to perform operations such as tilting the loading platform and rotating the drum. PTO is a device that extract the power for that from the engine. Normally, the engine is a necessary part for running, but by using the power of the engine through the PTO, it is also possible to operate the truck body without any other power sources. There are some other trucks that have PTO system, such as aerial work vehicles including crane trucks or fire trucks, and tractors or garbage trucks which may be more familiar to you.

Mechanism of Power Take Off
PTO (Power Take Off) generates power by changing engine rotation to “Hydraulic”. Hydraulic pressure is a mechanism that uses fluid called hydraulic fluid as an energy transmission medium. Hydraulic have the advantage of being able to move big thing with little power. It is also easy to operate because it can quickly move onto the operation once switched on, and also it is easy to adjust the force. Therefore, PTO is used on various work vehicles.

There are two types of PTO activation methods: switch type and lever type. Some types of PTOs that are activated by levers require clutch operations. Also, when PTO changes engine energy to hydraulic pressure, a part called “PTO shaft” is required. PTO shaft requires daily inspection and regular maintenances as they are subjected to be under heavy loads, and its deterioration can defect the PTO. Because the PTO shaft is heavy, please be careful not to hurt yourself during maintenance.

Types of PTO (power take-off)
There are three main types of PTO (power take-off).

1. “Transmission PTO”
As the name suggests, transmission PTO is attached to the side of the transmission.
This type can be activated only when the vehicle is stopped, so it is mainly installed in crane vehicles and aerial work platforms.

2. “Flywheel PTO”
Flywheel PTO is attached to the engine directly so it can be activated both the vehicle is stopped and running. It is mainly used for mixer trucks that require the drum to rotate while driving. Flywheel PTO is sometimes used in refrigerated and frozen vehicles that require temperature adjustment regardless of whether they are stopped or running.

3. “Full power PTO”
Full power PTO is installed between the engine and transmission. The full power PTO is designed to extract 100% of the engine power when the vehicle is stopped. For this reason, they are installed in vehicles that require particularly large power, such as dump trucks, vacuum cars, and fire trucks.