Printer having adjustable gap between print head and recording medium

Claim 1

A printer for printing on a recording medium, comprising: a platen for supporting the recording medium; a print head disposed opposite to said platen, for effecting a printing operation on said recording medium supported by said platen; a carriage movable in a direction parallel to said platen and supporting said print head; gap changeover means for moving said print head and said platen relative to each other in a direction toward and away from each other, and thereby adjusting a head gap between said recording medium supported by said platen and said print head; discriminating means for generating an output signal indicating that said recording medium includes a local portion whose thickness is larger than that of a remaining portion thereof; gap control means for controlling said gap changeover means such that said head gap is normally equal to a first head gap, said gap control means being responsive to said output signal of said discriminating means, for controlling said changeover means such that said head gap is changed to a second head gap which is greater than said first head gap; and printing speed control means for normally selecting a first printing speed at which said print head effects said printing operation, said printing speed control means being responsive to said output signal of said discriminating means, for selecting a second printing speed which is lower than said first printing speed wherein said printing speed control means comprises means for moving said carriage at a rate lower than that used for said first printing speed, and means for activating said print head at a frequency lower than that for said first printing speed to established said second printing speed.