A printer apparatus includes a print head, a platen roller having a rod, a spring configured to press the print head toward a direction of the platen roller, a frame having in a side face thereof a platen supporting groove for supporting the rod of the platen roller, and a detection switch, wherein the platen supporting groove includes a first edge situated toward a direction of the print head and a second edge situated opposite from the first edge, and has on the second edge a projection projecting toward inside the platen supporting groove, and wherein placing the rod of the platen roller at a predetermined position at a deeper side of the platen supporting groove than the projection causes the rod of the platen roller to press the detection switch due to an urging force that is applied to the platen roller by the spring through the print head.

A printer according to an embodiment includes: a printer body including a supplying part that rotatably holds a roll-shaped sheet member; an opening and closing cover configured to open and close with respect to the printer body; a thermal head disposed on the printer body, the thermal head configured to print on the sheet member; a platen roller disposed on the opening and closing cover, the platen roller positioned at a location opposite to the thermal head and feeding the sheet member in a closed configuration; and a platen roller holding mechanism configured to attachably and detachably secure the platen roller to the opening and closing cover. The platen roller holding mechanism includes a label roll supporter that rotatably guides the roll-shaped sheet member in the supplying part. The label roll supporter includes a cross-sectional arc-shaped surface.

A label printer according to an embodiment includes a support unit that supports a roll of a backless label paper; a conveying unit that conveys and reverse conveys the backless label paper along a conveying path; a printing unit positioned on the conveying path and including a print head that prints on a surface of the backless label paper; a cutting unit, positioned on the conveying path downstream of the printing unit in a conveying direction, that cuts the backless label paper; and a control unit that controls the conveying unit to reverse convey the backless label paper in a reverse conveying direction after the cutting unit cuts the backless label paper sheet so that a tip of the backless label paper is stopped at a predetermined position downstream from the print head in the conveying direction.

A tape cartridge is detachably installed on a cartridge installation portion of a tape printing apparatus having a platen supporting shaft and a printing head. A base end of the platen supporting shaft is fixed to the cartridge installation portion at one end of the platen supporting shaft. The tape cartridge includes the platen roller, the upper bearing portion, the lower bearing portion, and the fitting portion. The platen roller includes an upper and lower engagement portion. The upper bearing portion rotatable supports the upper engagement portion and restricts movement of the upper engagement portion. The lower bearing portion rotatable supports the lower engagement portion and restricts movement of the lower engagement portion. The fitting portion in which a tip end of the platen supporting shaft passing through the platen roller fits when the tape cartridge is installed on the cartridge installation portion.

A thermal printer includes a head block having a head support plate and a thermal head fixed to the head support plate, a platen roller brought into abutment against the thermal head through intermediation of recording paper, a wiring board drawn from the thermal head, a frame supporting the platen roller and the head support plate, and a recording paper sensor mounted to the wiring board and detecting the recording paper. The frame includes a guide wall arranged on upstream of the thermal head in a conveyance direction of the recording paper, the guide wall guiding the recording paper to the thermal head. The head block including a sensor holder mounted thereto, the sensor holder holding the recording paper sensor at a portion which is located between the thermal head and the guide wall in the conveyance direction.

A printer includes a print head, a platen roller, a frame, a release lever, and a spring. The print head performs printing on recording paper. The platen roller conveys the recording paper held between the platen roller and the print head. The print head and the platen roller are placed on the frame. The frame includes a side plate in which a frame groove is formed. The release lever moves relative to the frame. The spring is provided between the frame and the print head to urge the print head toward the platen roller. The platen roller is placed on the frame while being held between the frame groove and the release lever. The release lever moves to unblock the frame groove.

A printer includes a body, a lid pivotably attached to the body, a platen roller attached to the lid, and a lock lever. The body includes a print head and a holder to accommodate a roll of recording sheet. The lock lever supports a bearing of the platen roller when the lid is closed. The printer further includes a first plate and a second plate arranged on the lid in the widthwise direction of the printer, and a movable button provided on the lid. When the button is moved to slide the first and second plates toward each other, the outer end of each of the first and second plates in the widthwise direction moves inward to be positioned inside the outer frame of the holder to allow the closure of the lid.

A thermal printer with a thermal head including a heating element forms an image on a medium. The printer includes a temperature sensor that measures a temperature of the medium, a heater that heats an interior of the thermal printer, and a processor. The processor determines whether a temperature measured by the temperature sensor is equal to or greater than a preset temperature threshold, operate the heater if the measured temperature is less than the temperature threshold, and determine an application energy amount for the thermal head based on the measured temperature if the measured temperature is equal to or greater than the temperature threshold.

A printer includes a housing, a shaft connected to an inner surface of the housing at a first end thereof, extending along a first direction to a second end, and by which an ink ribbon is held, a print head connected to the surface at a first end thereof, extending along the direction to a second end, and transferring ink from the ribbon to a sheet, a roller connected to the surface at a first end thereof, extending along the direction to a second end, and conveying the sheet, and a holding plate connected to the second end of the roller and rotatable around a first hinge and by which the second ends of the shaft and the head are held when the plate is rotated about the first hinge to be parallel to the surface. The plate includes a second hinge about which the holding plate is foldable.

A printer has a print head, a cable harness connected to the print head, a head bracket detachably installed with the print head, a platen roller provided to face the print head, and a storage casing provided in one side of a feeding path and provided with a storage space in which the cable harness can be stored.