Painting Robot

Overview

A painting robot is a six-axis arm built to apply liquid paint inside a spray booth, where the air is full of flammable solvent vapour and overspray. Two features set it apart from a standard handling robot. First, the whole machine is explosion-protected: the arm and cabinet are sealed and held under a clean-air overpressure so vapour can never reach an ignition source inside. Second, the wrist is hollow, with the paint and air lines routed through the centre of the arm to the tool, so there are no external hoses to whip around, snag, or trap paint. It is the workhorse of automotive and appliance finishing lines, where it lays down an even coat at high speed and consistent quality.

How it works

The arm is six Servo Joint axes, each a sealed Servo Motor driving a Harmonic Reducer strain-wave gearbox with encoder feedback, carried on an Explosion-Proof Base certified for the hazardous zone. The fluid lines run inside the Hollow Wrist, whose central bore lets the wrist roll continuously without twisting external hoses. At the tip is the Rotary Bell Atomizer, a rotary bell atomizer: an air-bearing turbine spins a titanium Bell Cup to tens of thousands of rpm, flinging paint off its edge into an ultra-fine cloud, while a Shaping-Air Ring ring shapes that cloud onto the part. An HV Cascade charges the paint to tens of kilovolts so the droplets wrap around to coat edges and far sides, pushing transfer efficiency far above a hand spray gun.

Paint reaches the bell through the Fluid System, a servo gear pump meters exact volume, a regulator holds pressure, and fast trigger valves start and stop flow, fed by a color changer that selects and flushes between dozens of colors. The Purge Unit purge unit keeps the arm and cabinet over-pressurised and shuts the robot down if that pressure is lost. Outside the booth, the Controller Cabinet cabinet runs the motion controller, the per-axis servo drives, and a process board that coordinates fluid, bell speed, shaping air, and high voltage. Programs are taught and tuned from an intrinsically safe Teach Pendant.