An improved printer for selectively imprinting a clear pattern carried by a pattern carrier on an imprint receiver. The printer is provided with a pattern carrier, an imprint receiver for receiving the carried pattern, means for recording the pattern on the imprint receiver, at least one print hammer for striking the imprint on the imprint receiver and means for advancing the print hammer for striking the imprint on the imprint receiver.
A print wheel impact printer in a document encoder comprises a flexible shield (38) made from laminar polyester sheet, the shield (38) having a shielding portion (40) at either end of which is provided a folded portion (44), each folded portion (44) being operative by virtue of non-90 degree fold lines and by virtue of the folds (50,52) forming at least three sides of a polyhedron to support the flexible shielding section distant from the print wheel (14). The shielding portion (44) is maintained tilted relative to the line between the hammer (26) and the print wheel (14) thereby to provide an opening (68) wherethrough the ink ribbon may be passed when an ink ribbon cassette (10) is changed. In operation the flexible shielding portion (40) is moved and carried by the paper (30), driven by the hammer (26), against the ink ribbon (12) and print wheel (14) with the paper (30) protruding through an aperture (42) in the shielding portion (40). Extraneous marking or blemishes created on the paper by contact with the ribbon (12) are thereby avoided.
A printer mask has spaced openings to allow impact therethrough of a hammer against characters arranged in circular columns along a character drum. The distance between the characters and mask changes automatically to compensate for changes in ambient temperature by using mounting materials of selected thermal coefficients of expansion. Uniform printing quality without marring the print paper is achieved with this mask construction.
A printer having plural type font wheels for function symbols of different colors and plural type font wheels for numerals of different colors fitted on a rotary shaft, wherein the plural type font wheels for numerals are displaced along the shaft for each printing action. The plural type font wheels for function symbols or for numerals are provided with a mask for exposing only one type font wheel of a desired color but covering all other wheels to enable multi-color printing. The selection of the type font wheel for printing is achieved by the displacement of plural type font wheels in the digit direction with respect to the mask.
A dot matrix printer having a platen, a carriage, and a print head mounted on the carriage. A paper guide is secured to the carriage. A ribbon mask made of a resilient plate is attached to the paper guide. A cantilevered resilient plate is formed in the ribbon mask so as to be abutted on a front end of the print head to form a path for a ribbon between the resilient plate and the print head.
A printer provided with a plurality of printing type wheels, which have printing types at their periphery and can be selectively stopped at the printing position and a hammer disposed so as to be opposite to said printing type wheels, which can push recording paper against them, in which the hammer is made of a material of relatively hard synthetic resin and has a plurality of chevron shaped comb-like thrusting portions corresponding to the printing type wheels, each of the thrusting portions being constructed so as to include a hollow inside.
