How Does The Volvo Torque Converter Work?

You probably love Volvo models because of the strength they exude from the exterior design as well as the high performance their engines offer. But have you ever wondered why Volvo models feature engines that hardly ever fail. Chances are, you have. The answer boils down to the engine design and of course, torque. That’s where Volvo torque converters come into the picture. Without one, your Volvo automatic transmission won’t work.  Read on to learn more.

The Concept

Volvo models without automatic transmissions do not have clutches. They use torque converters instead. As such, they need an efficient way to let the engine run while the gears and wheels in the transmission halt or come to a stop. This is of course different in manual transmission Volvo models which use a clutch designed to disconnect the engine from transmission each time you engage or disengage a gear.

How It Works

The answer pretty much lies in the definition. A torque converter is simply a coupling that mostly relies on a fluid hydrodynamic to allow the car engine to spin independently without relying on the transmission. This means that when the engine is idling as it often does when you are at a stop light, the amount of torque running through the torque converter is relatively small but still enough to need pressure on the brake pedal to stop your car from creeping. So as soon as you release the brake pedal and step on the gas pedal, the engine quickly speeds up and pumps more fluid straight into the torque converter. This cases more power to be transmitted to the wheels.

The Design

The Volvo torque converter is made up of three main parts. There’s the impeller, the turbine and the stator. The impeller, which is also known as the pump, is filled with fluid. It is designed to spin with the engine crankshaft to ensure efficiency. The faster it spins with the engine crankshaft the more force it creates as fluid flows through it harder and faster.

Then there’s the turbine which forces the fluid into a turbine which is simply put, an assembly of blades. The turbine, which sits on the opposite side of the impeller, rotates as the fluid from the impeller hits its different blades. The fluid flowing through the turbine is repeatedly transferred from the exterior section to the interior section of the turbine. It is then returned to the impeller and the cycle continues. This constant circulation of fluid from the Volvo impeller to the turbine creates what experts refer to as ‘fluid coupling’

The Stator

The final part of the Volvo torque converter, which is the stator is just as important as the other two parts. It reverses the fluid and sends it back to the impeller. This slows down the fluid. Torque is then created as the transmission fluid flows into the impeller so as to keep the cycle going. Note that at this point, the fluid flows in a different direction, from where it first flowed when it came off the impeller. This is exactly where the starter comes in. It is simply a series of fins located between the transmission shaft and the two turbines. It has angled blades which make it easy for the rotor to reverse the direction of transmission fluid and channel it back to the impeller as it flows into the stator blades.  When the engine stops running, the stator’s one way clutch also stops spinning. This immediately breaks the hydrodynamic circuit.