A printer has a carriage being movable between a first end and a second end of a reciprocating path; and a driving force transmitting path selecting mechanism provided at the second end of the reciprocating path. The selecting mechanism has: a common driving force outputting member; a plurality of force receiving members; a selecting member; and a position retainer for keeping the position of the selecting member. The selecting member connects the force outputting member to one of the plurality of force receiving members, and moves in association with the carriage when the carriage moves in a vicinity of the second end in a first direction extending from the first end to the second end. The position retainer keeps the position of the selecting member when the carriage moves in a second direction extending from the second end to the first end. The force receiving member connected to the force outputting member via the selecting member is selected in accordance with a movement of the carriage along the reciprocating path.

A printer has a carriage being movable between a first end and a second end of a reciprocating path; and a driving force transmitting path selecting mechanism provided at the second end of the reciprocating path. The selecting mechanism has: a common driving force outputting member; a plurality of force receiving members; a selecting member; and a position retainer for keeping the position of the selecting member. The selecting member connects the force outputting member to one of the plurality of force receiving members, and moves in association with the carriage when the carriage moves in a vicinity of the second end in a first direction extending from the first end to the second end. The position retainer keeps the position of the selecting member when the carriage moves in a second direction extending from the second end to the first end. The force receiving member connected to the force outputting member via the selecting member is selected in accordance with a movement of the carriage along the reciprocating path.

A media processing device includes: a print head extending across a media path, and configured to apply indicia to media; a platen roller assembly adjacent to the print head, the print head configured to draw the media from a media supply along the media path travelling between the print head and the platen roller assembly, the platen roller assembly including: (i) a first platen roller extending across a first portion of a width of the media path, and (ii) a second platen roller coaxial with the first platen roller, and extending across a second portion of the width of the media path; a drive assembly coupled with the first and second platen rollers, the drive assembly configured to selectively drive rotation of either or both of the first and second platen rollers.

A media processing device includes: a print head extending across a media path, and configured to apply indicia to media; a platen roller assembly adjacent to the print head, the print head configured to draw the media from a media supply along the media path travelling between the print head and the platen roller assembly, the platen roller assembly including: (i) a first platen roller extending across a first portion of a width of the media path, and (ii) a second platen roller coaxial with the first platen roller, and extending across a second portion of the width of the media path; a drive assembly coupled with the first and second platen rollers, the drive assembly configured to selectively drive rotation of either or both of the first and second platen rollers.

A print system includes a head, a conveyance motor, a first connector, and a second connector, a power supply circuit. When a first power source is connected to the first connector and a second power source is connected to the second connector, the power supply circuit supplies at least some of a first power to the head and supplies at least some of a second power to the conveyance motor. The first power is a power of the first power source. The second power is a power of the second power source.

A print system includes a head, a conveyance motor, a first connector, and a second connector, a power supply circuit. When a first power source is connected to the first connector and a second power source is connected to the second connector, the power supply circuit supplies at least some of a first power to the head and supplies at least some of a second power to the conveyance motor. The first power is a power of the first power source. The second power is a power of the second power source.

A power supply apparatus comprises: a first power supply line; a second power supply line; a connection unit connecting the first and second power supply line and capable of operating in either a first operation mode in which power transmission between the first and second power supply lines is possible or a second operation mode in which power transmission is not possible; an electric discharge unit connected to the second power supply line and capable of operating in either a third operation mode in which a voltage of the second power supply line is dropped or a fourth operation mode in which the voltage is not dropped; a voltage monitoring unit to monitor the voltage of the second power supply line; and a control unit to control operation of the connection unit and the electric discharge unit.

A power supply apparatus comprises: a first power supply line; a second power supply line; a connection unit connecting the first and second power supply line and capable of operating in either a first operation mode in which power transmission between the first and second power supply lines is possible or a second operation mode in which power transmission is not possible; an electric discharge unit connected to the second power supply line and capable of operating in either a third operation mode in which a voltage of the second power supply line is dropped or a fourth operation mode in which the voltage is not dropped; a voltage monitoring unit to monitor the voltage of the second power supply line; and a control unit to control operation of the connection unit and the electric discharge unit.