Patent attributes
A shaft portion 2a of a platen roller 2 is inserted into an elongated hole-like recess 5a of a platen frame 5 so as to be movable therein. A release arm 9 having an engagement portion 9b engaged with a shaft portion 2a is swingably provided and is urged by a spring member 10. A switch 11 has an intercept 11a which can be contacted/separated to/from the release arm 9. When a thermal head 1 is moved against a spring force of a spring member 4, the release arm 9 follows the thermal head 1 to be allowed to swing by the spring member 10, thereby moving the shaft portion 2a in the recess 5a. When the switch 1 detects movement of the release arm 9, it is determined that recording is impossible since the thermal head 1 and the platen roller 2 are spaced apart from each other.
