GB992590A - High speed printers with column spanning hammers - Google Patents

Abstract

992,590. Selective printers. POTTER INSTRUMENTS CO. Inc. Nov. 24, 1961 [Nov. 25, 1960], No. 42142/61. Heading B6F. [Also in Division G4] A high-speed printer wherein a number of type faces are moved past printing positions in a printing line has a printing hammer which spans at least two type positions on the printing line, the arrangement of type faces being such that they register with the hammer one at a time, and the hammer being operated each time a required type face is in register therewith. As shown in Fig. 1, each hammer such as 13 spans three circumferential rows of type 6, 7, 8 on a continuously rotating cylinder 1, each row comprising a complete set of characters to be printed, and the type faces being staggered circumferentially so that only one type face at a time is in register with a hammer. For each complete line of printing, the cylinder makes three revolutions, and the timing of the hammer 13 is such that during the first revolution it prints a selected type in row 6, during the second revolution it prints a selected type in row 7, and in the third revolution a character is printed in row 8, this cycle being repeated for the next line. Rotating with the cylinder 1 are a hammer tone wheel 22 and clock tone wheel 34. A fixed contact 37 engages contact segments 35 on the wheel 34 so as to transmit tc a counter 41 a pulse for each character passing the printing line, and the character count is applied to comparators 52, 53, 54, one for each character row, connected to storages 60, 67, 74 to which information regarding characters to be printed is supplied. The wheel 22 has contact segments 23 co-operating with fixed contacts 24, 25, 26 corresponding to the three rows and provides timing signals to the hammer operating circuits. By suitable circuitry (see Divisior G4) the operation of the hammers is effected as required. In a modified construction (Fig. 4 not shown), each hammer spans two rows of type and is moved axially a distance corresponding to two rows of type after printing from the first two rows, and then prints from the adjacent two rows, so that four revolutions of the cylinder are required for each line of print. Type on endless bands. According to another construction, Fig. 2, the type are arranged on an endless band 117 in repeated sets of three, each type being separated from the next by three letter spaces and each hammer 124. . . 129 spanning three letter spaces. The paper moves perpendicularly to the band 117 for line spacing, and a complete line is printed during three complete traverses of the belt, each hammer being operated once during each traverse. In a modification of this construction (Fig. 3, not shown), the band is provided with one set of characters only, the spacing of the characters and the span of each hammer being three letter spaces. In this case, a line is printed during one complete traverse of the band, and if a particular character is required to be repeated in adjacent column positions, a hammer is actuated twice in quick succession as the character passes over it.