US 4,534,665 AGranted

Serial printer

AssigneesEpson Corporation, Kabushiki Kaisha Suwa Seikosha

InventorsMasahiko Mori, Kenichiro Arai, Chikao Tezuka

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Abstract

A multicolor serial printer has a color switching means interposed between an end of a carriage and type wheels having a group of first-color printing types and a group of second-color printing types. The color switching means has first-color and second color printing stepped surfaces selectively movable into confronting relationship with a member of the carriage. When the member of the carriage abuts on and engages in a first-color printing stepped surface or a second-color printing stepped surface during carriage shifting movement, a presser of a hammer means, mounted on the carriage and positioned within the type wheels, is brought into confronting relation to the group of first-color printing types or the group of second-color printing types for printing a desired character in the group in a first or second color.

Claims12

Dependent claims

A serial printer comprising:

print wheels in the form of annular rings supported on a common holder, said print wheels including a plurality of raised type positioned on and spaced around the outer peripheral surface of each said annular ring, said print wheels including at least a first group of printing types and a second group of printing types, each said printing types having a face;
a rotatable shaft supporting said print wheels on said common holder for corotation of said print wheels;
hammer means having a presser for selectively confronting and pressing the types of said print wheels from inside said annular rings to press the face of a selected type on a sheet of recording paper;
a platen, said recording paper being positioned between said platen and said print wheels;
a carriage having mounted thereon said hammer means for laterally shifting said hammer means therewith successively from one print position to the next, said print wheels being mounted on said carriage;
and
switching means for selectively bringing said presser of said hammer means into confronting relationship to a print wheel of said first group of printing types or alternatively in confronting relationship to a print wheel of said second group of printing types, said confronting relationship being determined during a lateral shifting stroke of said carriage between one printing position and the next printing position, wherein said carriage includes an engaging member fixedly attached thereto, said switch means including:
a first cam for translating said print wheels axially on said shaft, said first cam having a first stepped surface for engaging with said engaging member of said carriage during a lateral shifting stroke of said carriage to position said presser in confronting relationship to a print wheel of said first group of print types, and a second stepped surface for alternatively engaging with said member of said carriage during said lateral shifting stroke of said carriage to position said presser in confronting relationship to a print wheel of said second group of print types;
a second cam engageable with said first cam for rotating said first cam, and
means for stopping rotation of said second cam so as to selectively position said engaging member of said carriage into confronting relationship to said first stepped surface or alternatively to said second stepped surface.

7 more elements

A serial printer comprising:

a plurality of print wheels of flexible material in the form of annular rings, said print wheels each including plurality of raised type positioned on and spaced around the outer peripheral surfaces of said annular rings;
a platen positioned in opposition to said print wheels and spaced therefrom;
movable support means for holding said print wheels, said support means being of an open structure allowing access to the backside of each said raised type, said support means when moving in a first mode causing each said raised type to move to oppose in sequence said platen;
means for moving said support means in said first mode and for stopping said support means with a selected one of said raised type opposing said platen;
impact means for impacting the accessible backside of said selected one of said raised type, said impact flexing and extending said annular ring and pressing the face of the selected type against said platen;
a carriage mounted for lateral translation relative to said platen with said print wheels, support means and impact means being supported on said carriage and moving therewith, whereby a line of selected type can be printed on said print medium;
indexing means for moving said support means in a second mode, said second mode being translation of said support means with said print wheels in said lateral direction relative to said impact means, said impact means impacting the accessible backside of types on different annular print wheels dependent upon the relative lateral position of said support means;
and
wherein the number of lateral positions of said support means relative to said impact means is at least two and further comprising means to initiate said lateral translation of said support means relative to said impact means when said carriage laterally translates to a preselected position, and
wherein the number of said lateral positions of said support means relative to said impact means is at least three and wherein said means to initiate said latest translation of said support means comprises switching means for selectively bringing said support means from the first lateral position to the second lateral position when said carriage laterally translates to said preselected position, or alternatively to bring said support means to said third lateral position from said first lateral position when said carriage laterally translates to said preselected position, a different print wheel being aligned to said impact means at each lateral position of said support means, and
further comprising a shaft, said print wheels being mounted on said shaft for rotation therewith and for axial motion therealong;
said indexing means including:
a first cam for translating said print wheels axially on said shaft, said first cam having a first step surface for engaging a fixed member of said carriage during a lateral shifting stroke of said carriage to said preselected position, said impact means being aligned with the second said lateral position of said support means, and a second step surface for alternatively engaging with said carriage member during lateral shifting of said carriage to said preselected position, said impact means being aligned to the third lateral position on said support means.

10 more elements

Dependencies are inferred from the claim text.