A printer includes a case including an input port for rolled paper, a cover provided to be rotatable between a closed position of the input port and an open position of the input port, a holding portion that holds the rolled paper, a biasing member that biases the holding portion in a first direction, a stopper mechanism that stops rotation of the holding portion in the first direction, and a linkage mechanism that rotates the holding portion in conjunction with the rotation of the cover. When the cover is in the closed position, the holding portion rotates in the first direction in accordance with an outer diameter of the rolled paper by a biasing force of the biasing member. When the cover rotates from the closed position to the open position, the holding portion rotates together with the cover against the biasing force of the biasing member.

A printer includes a case including an input port for rolled paper, a cover provided to be rotatable between a closed position of the input port and an open position of the input port, a holding portion that holds the rolled paper, a biasing member that biases the holding portion in a first direction, a stopper mechanism that stops rotation of the holding portion in the first direction, and a linkage mechanism that rotates the holding portion in conjunction with the rotation of the cover. When the cover is in the closed position, the holding portion rotates in the first direction in accordance with an outer diameter of the rolled paper by a biasing force of the biasing member. When the cover rotates from the closed position to the open position, the holding portion rotates together with the cover against the biasing force of the biasing member.

An expansible chuck for holding hollow cylindrical cores used for winding and unwinding sheet material. A portion of the chuck body nearest the flange is stepped up so that the diameter of the chuck near the flange is slightly larger than the diameter of the rest of the chuck. The stepped up portion centers the chuck within the core which helps the expanding elements to uniformly grip the core.

An expansible chuck for holding hollow cylindrical cores used for winding and unwinding sheet material. A portion of the chuck body nearest the flange is stepped up so that the diameter of the chuck near the flange is slightly larger than the diameter of the rest of the chuck. The stepped up portion centers the chuck within the core which helps the expanding elements to uniformly grip the core.

A sheet conveyor includes: a holder that detachably holds a sheet roll; a rotation measuring device that measures a rotation amount of the sheet roll; a conveyance roller that conveys a sheet pulled out from the sheet roll held by the holder; a tensioner that is provided between the holder and the conveyance roller and that contacts with the sheet pulled out from the sheet roll toward the conveyance roller; a position detector that detects a position of the tensioner; a motor that generates driving force for rotating the conveyance roller; and a controller that controls the motor. The controller estimates a diameter of the sheet roll based on a conveyance amount of the sheet caused by rotation of the conveyance roller, a rotation amount of the sheet roll measured by the rotation measuring device, and a position of the tensioner detected by the position detector.

A sheet conveyor includes: a holder that detachably holds a sheet roll; a rotation measuring device that measures a rotation amount of the sheet roll; a conveyance roller that conveys a sheet pulled out from the sheet roll held by the holder; a tensioner that is provided between the holder and the conveyance roller and that contacts with the sheet pulled out from the sheet roll toward the conveyance roller; a position detector that detects a position of the tensioner; a motor that generates driving force for rotating the conveyance roller; and a controller that controls the motor. The controller estimates a diameter of the sheet roll based on a conveyance amount of the sheet caused by rotation of the conveyance roller, a rotation amount of the sheet roll measured by the rotation measuring device, and a position of the tensioner detected by the position detector.

A system to monitor available media in a printer is disclosed. The system may include a media holder that includes a support frame and a support member that extends from the support frame. The support member may be configured to receive a media roll. The system may include an optical sensor attached to the support frame of the media holder. The optical sensor may be configured to include an axial end of the media roll within a field of view of the optical sensor. The optical sensor may be configured to output sensor data that indicates whether the media roll has available media according to a radius of the axial end.

A system to monitor available media in a printer is disclosed. The system may include a media holder that includes a support frame and a support member that extends from the support frame. The support member may be configured to receive a media roll. The system may include an optical sensor attached to the support frame of the media holder. The optical sensor may be configured to include an axial end of the media roll within a field of view of the optical sensor. The optical sensor may be configured to output sensor data that indicates whether the media roll has available media according to a radius of the axial end.

The present invention provides a label printer, including an upper cover module and a bottom case module configured to cooperate with the upper cover module in printing. An elastic wall is disposed at an articulating part between the upper cover module and the bottom case module. An inclined surface is provided at a corresponding position of the lower cover module. When the upper cover is opened upward to the maximum extent, a tail end of the elastic wall cooperates with the inclined surface to form a support structure to prevent the upper cover module from falling due to the gravity and the like when the upper cover module is opened.

The present invention provides a label printer, including an upper cover module and a bottom case module configured to cooperate with the upper cover module in printing. An elastic wall is disposed at an articulating part between the upper cover module and the bottom case module. An inclined surface is provided at a corresponding position of the lower cover module. When the upper cover is opened upward to the maximum extent, a tail end of the elastic wall cooperates with the inclined surface to form a support structure to prevent the upper cover module from falling due to the gravity and the like when the upper cover module is opened.