Patent ID: 6406110
Filing Date: 2002-06-18
Classification: B41J

Abstract:
An imaging apparatus having a printhead positioned above a print media support, wherein a print medium passes therebetween during printing, comprising:a first side frame and a second side frame, said second side frame being spaced apart from said first side frame; a guide rail extending between said first side frame and said second side frame; a guide rod having a first end, a second end and an axis, said guide rod extending between said first side frame and said second side frame, said guide rod positioned to be substantially parallel to said guide rail; a printhead carrier for carrying said printhead, said printhead carrier having a slotted portion for slideably engaging said guide rail and having a bearing for slideably engaging said guide rod; a first eccentric bushing assembly for movably mounting said first end of said guide rod to said first side frame, and a second eccentric bushing assembly for movably mounting said second end of said guide rod to said second side frame, wherein each of said first eccentric bushing assembly and said second eccentric bushing assembly include a stationary portion and a rotatable portion; a gap spacing adjustment mechanism coupled to at least one of said first eccentric bushing assembly and said second eccentric bushing assembly for effecting a change in position of said guide rod in a direction normal to said axis so as to adjust a gap spacing between said printhead and said print medium; and a driven gear attached to said rotatable portion of one of said first eccentric bushing assembly and said second eccentric bushing assembly, said driven gear being driven by said gap spacing adjustment mechanism, wherein said gap spacing adjustment mechanism includes a ratchet mechanism and a drive gear coupled to said ratchet mechanism, said ratchet mechanism providing selective rotation of said drive gear in a first rotational direction, said drive gear being positioned for engaging said driven gear to rotatably drive said driven gear.