Thermal printer for a low cost electronic mail terminal

A printer for printing characters onto thermally sensitive paper, said printer comprising:

• means forming a base having a planar surface;
• a first plate coupled to said base and disposed substantially perpendicular to said surface of said base, said first plate including:
• upper and lower motor brackets affixed to said first plate for mounting said first motor thereon, said upper and lower motor brackets being deflectable to accommodate installation of said first motor;
• and
• upper, central, and lower pulley brackets affixed to said first plate for mounting said first pulley thereon, said lower pulley bracket having a recess therein that is open to the top, said central pulley bracket having a slot therein disposed above said recess, and said upper pulley bracket being disposed above said slot and recess and deflectable to a position not above said slot and recess;
• a second plate coupled to said base and disposed laterally spaced apart from and approximately parallel to said first plate;
• a first shaft disposed between and rotatably coupled to said first and second plates, said first shaft being disposed approximately parallel to said surface of said base and carrying at least one paper engaging roller;
• a second shaft disposed between and coupled to said first and second plates and disposed parallel to said first shaft;
• means forming a platen disposed between and coupled to said first and second plates and disposed parallel to said shafts;
• means forming a passageway between said platen and said first and second shafts for receiving a continuous web of paper;
• a carriage slideably coupled to said first and second shafts;
• print head means removeably coupled to said carriage and operable for locally heating said paper to transfer a character pattern thereto;
• carriage positioning means coupled to said plates and to said carriage for laterally positioning said carriage along said shafts, said belt drive means including a first rotary electric motor having a shaft with a drive roller affixed thereto, said first motor being coupled to said first plate such that the periphery of said drive roller is in rolling contact with the periphery of said lower portion of said first pulley, said first motor being operable for rotating said first pulley;
• a first pulley coupled to said first plate and rotatable about an axis perpendicular to said shafts, said first pulley having an upper portion and a lower portion;
• a second pulley coupled to said second plate and rotatable about an axis parallel to said axis of said first pulley, said second pulley being coupled to said second plate by a dowel pin disposed at the axis of said second pulley, said dowel pin being retained in a groove in said second plate by said secod shaft;
• belt means for translating said carriage in response to rotation of said first pulley, said belt means forming a loop around said upper portion of said first pulley and said second pulley with both ends thereof being affixed to said carriage;
• and
• belt drive means coupled to said lower portion of said first pulley for rotating said first pulley.

A printer for printing characters onto thermally sensitive paper, said printer comprising:

• means forming a base having a planar surface;
• a first plate coupled to said base and disposed substantially perpendicular to said surface of said base;
• a second plate coupled to said base and disposed laterally spaced apart from and approximately parallel to said first plate, said second plate including two motor brackets affixed thereto for mounting said second motor thereon, said motor brackets being deflectable to permit the installation of said second motor;
• a first shaft disposed between and rotatably coupled to said first and second plates, said first shaft being disposed approximately parallel to said surface of said base and carrying at least one paper engaging roller;
• a second shaft disposed between and coupled to said first and second plates and disposed parallel to said first shaft;
• means forming a platen disposed between and coupled to said first and second plates and disposed parallel to said shafts;
• means forming a passageway between said platen and said first and second shafts for receiving a continuous web of paper;
• a carriage slideably coupled to said first and second shafts;
• print head means removeably coupled to said carriage and operable for locally heating said paper to transfer a character pattern thereto;
• carriage positioning means coupled to said plates and to said carriage for laterally positioning said carriage along said shafts, said carriage positioning means including,
• a first pulley coupled to said first plate and rotatable about an axis perpendicular to said shafts, said first pulley having an upper portion and a lower portion;
• a second pulley coupled to said second plate and rotatable about an axis parallel to said axis of said first pulley, said second pulley being coupled to said second plate by a dowel pin disposed at the axis of said second pulley, said dowel pin being retained in a groove in said second plate by said second shaft;
• belt means for translating said carriage in response to rotation of said first pulley, said belt means forming a loop around said upper portion of said first pulley and said second pulley with both ends thereof being affixed to said carriage;
• and
• belt drive means coupled to said lower portion of said first pulley for rotating said first pulley;
• and
• paper advance means coupled to said second plate and to said first shaft for rotating said first shaft thereby causing said roller to advance said paper through said printer.