Seiko Instruments Inc

Kimitaka Hirai

Noriyoshi Shoji

Akihiko Ito

Hideki Watanabe

Akio Naito

Shuji Tozaki

Katsuari Sato

A thermal printer has a thermal head pivotally mounted on a main body frame to pivot toward and away from a platen roller. The platen roller has shaft bearings at opposite ends thereof that are removably inserted in two spaced-apart opposed slots formed in the main body frame to rotatably support the platen roller. First springs bias a pivotal lock arm to a locked position to prevent removal of the shaft bearings from the slots, and second springs bias the thermal head toward the platen roller. Manual pivotal movement of the lock arm to an unlocked position permits removal of the shaft bearings from the shaft. The biasing directions of the first and second springs are parallel, which reduces the stroke distance of the first springs resulting in size reduction of the thermal printer.

Thermal printer

A thermal printer has a thermal head mounted on a case main body and a platen roller confronting the thermal head. A cover member mounted to the case main body undergoes swinging movement to open and close an opening of the case main body. A slider rotatably supports the platen roller and is mounted to the cover member for linear movement on a plane including a rotational center of the platen roller and a swing center of the cover member. Engagement pieces mounted to the slider engage with engagement portions of the case main body when the cover member closes the opening of the case main body and the platen roller confronts the thermal head. A biasing member biases the slider such that the engagement pieces engage with the engagement portions of the case main body and the platen roller is brought into pressure contact with the thermal head.

There is provided a thermal printer () including: a main body frame (); a thermal head () swingably mounted to the main body frame (); a platen roller () disposed to be opposed to a printing surface () of the thermal head (), for sandwiching a thermal paper with the thermal head () to feed the thermal paper; a lock arm () swingably mounted to the main body frame (), for locking the platen roller () with the main body frame () by pressing a shaft bearing () which rotatably supports the platen roller () against the thermal head (); a first spring () disposed between the lock arm () and the thermal head (), for biasing the platen roller () in a direction in which the platen roller () moves toward the thermal head (); and a second spring () disposed between the thermal head () and the main body frame (), for biasing the thermal head () in a direction in which the thermal head () comes into close contact with the platen roller (), in which the first spring () is disposed so that the first spring () applies a biasing force to the lock arm () at a position where the first spring () is closer to a swing center () of the lock arm () than the second spring () is.

There is provided a thermal printer () including: a main body frame (); a thermal head () mounted to the main body frame (); a platen roller () disposed to be opposed to a printing surface () of the thermal head (), for sandwiching a thermal paper () with the thermal head () to feed the thermal paper (); a lock arm () swingably mounted to the main body frame (), for locking the platen roller () with the main body frame () by pressing a shaft bearing () which rotatably supports the platen roller () against the thermal head (); a swing arm () that supports the shaft bearing () of the platen roller (), and swings between a lock position by the lock arm () and a release position apart from the lock arm (); and a lever () movably provided to the swing arm (), for releasing a locked state of the platen roller () by the lock arm () by an external force applied to a force point (), in which a direction in which the force point () of the lever () moves when the locked state by the lock arm () is released is same as a swinging direction of the swing arm ().

A thermal printer has a main body frame and a platen roller rotatably and removably mounted in a preselected position on the main body frame. A thermal head is mounted on the main body frame for movement into and out of pressure contact with the platen roller during a printing operation and while the platen roller is in the preselected position for recording printing data on a recording medium disposed between the thermal head and the platen roller. A detecting device detects a preselected state of the thermal printer in which the platen roller is in the preselected position and in which the recording medium is disposed between the platen roller and the thermal head.

Growing community of inventors

Chiba, Japan

Kimitaka Hirai