Be suitable for big thermal printer of print span

The utility model provides a be suitable for big thermal printer of print span includes main part support, printhead assembly, roller and pretightening component, printhead assembly with the roller isestablished in the main part support, and is equipped with recording paper transfer passage between the two, pretightening component with printhead assembly elastic connection, pretightening component is right printhead assembly applys the pretightning force, and pretightning force direction orientation the roller, printing state, the roller with printhead assembly, recording paper form the linecontact on the typing line, the perpendicular bisector of typing line is for printing the central line, pretightening component includes a plurality of elastic components, and is a plurality of the [coefficient of] stiffness of elastic component is the same, and is a plurality of the elastic component uses the printing central line to call to distribute as symmetric pair, printhead assembly is bigmore near printing the pre