Optimising Vehicle Paint Process for Improved Efficiency

Optimising Vehicle Paint Process for Improved Efficiency

Optimising Paint Vehicle Paint Process for Improved Efficiency

The new Airless Paint Automiser by Toyota Motor Corporation achieves over 95 % vehicle paint coating efficiency and is claimed to reduce global CO2 emissions by around seven percent

Among the most critical operations conducted during a new vehicle development, paint job processes have traditionally been cumbersome as well as a very time consuming one. Toyota Motor Corporation has recently introduced a new vehicle body painting technique has replaced conventional air paint atomisers with airless paint atomiser. The new technique deploys static electricity against the traditionally used air in the atomiser to achieve over 95 percent coating efficiency (the amount of paint sprayed versus the amount that actually adheres onto the vehicle body). This is significantly higher than conventional processes that delivers 60-70 % efficiency. Toyota claims that the new design in paint processes gets collection device at the bottom of the paint booth and can overall reduce CO2 emissions by up to seven percent.

Conventional air paint atomiser banks on aerodynamic force to paint the vehicle body with the atomised particles using an air paint atomiser. The process resulted in scattering of paint particles by air ricocheting off the vehicle body, thereby leading to up to 70 % coating efficiency. Such excessive scattering of paint particles is significantly reduced under the new airless paint atomiser technique. The new process uses electricity to spray paint (electrostatic automisation) that gravitate statically charged particles coat on the vehicle body, thereby leading to higher efficiency.

The tip of the airless paint atomiser features a rotating cylindrical head that optimises the amount of paint sprayed. According to the company, approximately 600 special grooves are inserted into the tip, which is rotated to create a centrifugal force, inducing the paint to flow into the grooves and atomise through static electricity. The unevenness of the vehicle body causes the distance between the cylindrical head and the vehicle body to fluctuate, making the electrical current unstable.

Interestingly, the airless paint atomiser constantly monitors the variations in current and automatically controls the voltage, maintaining a distance of approximately 10 centimeters between the cylindrical head and the vehicle body. Hence, electrostatic atomisation and electrostatic painting under a fixed current is rendered possible, in turn preventing variation in the size of the paint particles―the result is high-quality painting.

Toyota has developed the airless paint atomiser and deployed the same at both Takaoka and Tsutsumi Plants. Gradual deployment at other plants is planned as well as consideration of deployment among other Toyota Group companies and licensing the technology to other companies. Toyota aims to advance its initiatives to achieve its Plant Zero CO2 Emissions Challenge, one of the targets included in the Toyota Environmental Challenge 2050 announced in 2015.