US Patent 7280235 Print engine for double-sided printing

A print engine for double-sided printing includes a chassis. A pair of substantially identical inkjet printhead assemblies is mounted on the chassis opposite each other. A pair of transfer rollers is mounted on the chassis and positioned with respect to the printhead assemblies to permit an inkjet printing operation to be carried out on the transfer rollers. The transfer rollers define a contact region through which a sheet of print media is fed to receive the print. A pair of cleaning stations is operatively engaged with the transfer rollers to clean the transfer rollers subsequent to the print being transferred to the sheet.