It's not quite a hybrid since I see no reference to storage. It's more like a modern locomotive powertrain.
Thorne was a company that made generators so they were familiar with electronics of the 1930s. It was more of a truck built around a creatively simple drive system. A generator bolted to the flywheel of a gasoline engine made electricity that drove an electric motor bolted to a differential. A hallmark of the drive system was simple operation and low maintenance.
Crist’s 36’ Thorne model C-1 (concept truck), that was used by Rutter’s for 18 years, was never mass produced; however, the drive system lived on in other trucks made by Thorne and lives on today in large diesel locomotives.