Patent ID: 7731436

Claim:
An image forming apparatus, comprising: a thermal printing head (TPH) to form an image on a printing medium; a platen roller disposed to form a printing nip with the TPH; feed rollers provided on a first side and a second side of the TPH along a path that the printing medium travels to feed the print medium across the nip in a first direction and a second direction of the path so that the TPH forms a first portion of the image on a first portion of a first side of the printing medium when the printing medium is fed in the first direction and a second portion of the image on a second portion of the first side of the printing medium where the printing medium is fed in the second direction for the first time after printing the first portion of the image on the first portion of the first side of the printing medium; a frame having a lateral plate; a supporting bracket rotatably supported by the lateral plate to support the TPH; and a rotation cam to control the supporting bracket with respect to the lateral plate to transfer the TPH to a first position where the TPH can print on a first side of the printing medium and a second position where the TPH can print on a second side of the printing medium.