Evolved Liquid Hydrogen-Powered GR Corolla to Participate in Super Taikyu Fuji 24 Hours Race

1. Improved durability of liquid hydrogen pump

The durability of the pump, which boosts the pressure of liquid hydrogen before sending it to the engine, has been greatly improved in the hopes of completing the 24 Hours Race without the need for replacement. The pump was replaced twice during last year's 24 Hours Race.

The liquid hydrogen-powered engine generates power by injecting hydrogen, the fuel, directly into the engine for combustion. The liquid hydrogen-powered GR Corolla uses a reciprocating pump that pumps the fuel, converted to a gas inside the car, through the reciprocating motion of a piston when transferring hydrogen from the fuel tank to the engine. Because of the high pressure range this pump generates, the bearings which allow smooth rotation of the shaft and gears on one side of the crank, which transfers torque to the motor by converting reciprocating motion into rotational motion, were unevenly loaded, causing them to wear out and degrade quickly.

This time, a dual-drive crank mechanism has been implemented to improve the pump's durability. The application of motor torque from both ends of the crank enables the boosting piston to move in a well-balanced manner, thereby significantly increasing pump durability.