Patent GB-707736-A (GB)
Title: Improvements in or relating to a method of and apparatus for defining characters on impression receiving material
Inventor: JOHNSON WILLIAM EDWARD
IPC: B41J25/00
Filed: 1950-07-14
Abstract: 707,736. Writing-machines. POWERS-SAMAS ACCOUNTING MACHINES, Ltd. June 19, 1951 [July 14, 1950], No. 17716/50. Class 146(3) A method of defining characters consists of the steps of moving impressionreceiving material, e.g. paper, at a constant linear speed between the marking end of a stylus and a platen, reciprocating the marking end of a stylus in a straight line path substantially parallel to the plane of the impression-receiving material, applying impulses to the stylus at predetermined intervals during reciprocation to effect axial movement of the stylus towards the platen, and so selecting the length of the path of reciprocation of the stylus and the linear speed of the impression-receiving material that one determines the maximum width and the other the maximum height of the characters. As shown in Figs. 1A and 4, a plurality of styluses 11, each consisting of a thin steel rod having a flattened or rounded end 12, are slidably mounted in guides 13 for axial movement towards and away from a platen 15 over which passes a carbon ribbon 42 and a paper web 41 fed at a constant linear speed. The styluses are reciprocated transversely of the web 41 by a plate 18 through an eccentric strap operated by an electric motor which also drives a shaft carrying a plurality of character determining discs 26, Fig. 6. For example, thirty-nine discs may be provided, each representing a letter of the alphabet, and the numerals 1 to 9 and four selected characters, such as a plus and a minus sign. Perforated record cards are fed singly from a magazine to a position beneath a sensing head carrying sensing pins which sense the perforations, the sensing pins passing through perforations, thus completing electric circuits containing one or more relays. In the case of a card having twelve data positions for each vertical card column twelve relays are provided, the relays having certain contacts closable by a rotating switch. When these contacts are closed, current flows via one of the character determining discs 26 having electrical contacts cooperating with a fixed brush, to a coil 39, Fig. 4, wound around a permanent magnet 37 axially slidable within a casing 35 having a pole piece 36, such that energization of the coil causes outward axial'movement of the magnet 37 and a stylus 11 attached thereto, the stylus rebounding into retracted position upon de-energization of the coil. Since the stylus is reciprocating transversely of the paper web 41, Fig. 1A, the stylus thus forms a series of dots and lines on the strip according to the dispcsition of the contacts on the disc 26. For example, the letter A Fig. 7, is constituted by the dots 26a to 26cc which correspcnd to the relative disposition of the contacts 26a to 26cc, Fig. 6, on the disc 26. After the formation of a letter, the rotating switch opens the closed contact of the energized relay. In a modification, the character determining discs 26 may be replaced by drums having magnetically imprinted spots capable of carrying a small current which is amplified in order. to actuate the coils 39. The impulses imparted to the coils 39 may also be initiated by a punch unit of a summary punch unit operated by a tabulating machine or by the result-indicating unit of a multiplying machine, instead of by perforated cards. The stylus may be supplied with marking material supplied with a wick, thus forming the dots and lines directly instead of through the carbon ribbon. According to the Provisional Specification, the stylus may be replaced by a ballpoint pen.