Thermal printer

Claim 1

In a printer having a housing provided with paper input side, a paper exit side, and printer components arranged in said housing including a ribbon cassette having an ink ribbon wound on reels therein, a translatable carriage, a printing head mounted on the carriage for printing by transferring ink from the ink ribbon onto a paper, means for moving the ink ribbon in front of the printing head from and to the ink ribbon cassette, and means including a feed roller for feeding paper from the paper input side, past the printing head, and out the paper exit side, the improvement comprising: said housing having a body portion containing all of said printer components on one side thereof, and a bottom paper guide plate facing said body portion which is substantially planar extending from said paper input side to said paper exit side; said body portion having said printing components arranged therein such that respective paper contacting surfaces of said printing head, ink ribbon, and feed roller are substantially in one plane facing said bottom paper guide plate, and such that said feed roller is located downstream in a paper feeding direction from said printing head toward said paper exit side, said ink ribbon cassette having a longitudinal side is parallel with said one plane of said paper contacting surfaces, and said bottom plate having provided thereon a flat paper-pressing spring member located opposite the paper contacting surface of said feed roller and a flat platen located opposite the paper contacting surfaces of said ink ribbon and printing head, whereby said printer can be formed with a thin shape and paper can be fed into said printer, printed on, and fed out of said printer along a substantially planar path.