Patent ID: 8727462

Claim:
A marking head comprising: a tube-shaped casing of which both ends are opened; a plurality of pins which are received inside the casing so that the length direction thereof follows the axial direction of the casing and are respectively movable in a reciprocating manner in the axial direction; a heater which heats the plurality of pins; a thermal transfer tape which faces the plurality of pins in the axial direction; and an extruding member which extrudes the plurality of pins toward the thermal transfer tape so that the plurality of pins are pressed against the thermal transfer tape, wherein the casing includes an inner peripheral surface which is formed in a polygonal shape when viewed from the axial direction, wherein the plurality of pins are respectively arranged so as to take a posture parallel to the axial direction inside a region surrounded by the inner peripheral surface, and wherein in this arrangement, a plurality of rows of the pins arranged in a predetermined direction are arranged in a direction perpendicular to the row direction of the pins, the adjacent pins in the adjacent rows are respective offset from each other in the row direction of the pins, and each pin contacts the pins adjacent thereto.