Clutch Cargo?
Mr. Gillette's Synchro-Vox system was used in Clutch Cargo to combine live-action human lips with animated drawings. To make the characters speak, the lips of a live human actor were filmed and then superimposed over the motionless drawings of the character's face.* To further cut costs, action was simulated using clever wiggling of the camera or the drawing itself. Walking or running was accomplished by showing the character from the waist up, to eliminate complicated leg animation. The use of real live objects, again superimposed, also helped to keep costs down. Real smoke was used for explosions and an actual balloon substituted for a bubble-gum bubble.
*Kind of like Greta van Susteren, post-facelift.
Side note: I feel old knowing what Clutch Cargo is.