869,887. Typewriters; strip perforating ma. chines. BAFOUR, G. P., BLANCHARD, A. R., and RAYMOND, F. H. June 19, 1957 [June 20, 1956], No. 19378/57. Classes 100(3) and 100(4) Typewriter with perforating apparatus. A printing device 1 for producing symbols on a record R comprises a number of manually actuable keys, wherein the number of different symbols that the device can print on the record R is less than the number of keys, i.e. at least two keys cause the same symbol to be produced, but one key gives the symbol one characteristic whereas the other key gives the symbol a different characteristic. The device is described in relation to a typewriter comprising a bank of typelevers 1 controlled by a distributor or sequence switch 214 and the keys of a main keyboard 2. Simultaneously with the typing by the typewriter the keys control a code recorder 8 and a perforator 9 recording on a tape 10 for use in the automatic control of a type composing machine. The capacity of the main keyboard 2 of an ordinary typewriter is insufficient to accommodate the requirements of a composing machine and an additional lateral keyboard 3 and a service keyboard 4 with additional case-shift keys 5, 6 and 7 are provided. The actuation of keys 5, 6, 7 control the case-shift mechanism (see below) to shift either the type-basket or the platen on the one hand, and may control a selection device for the characterisation of the characters and signs which will be later depressed on the other hand. The characterisation of the symbols may consist in a change of colour of the typed characters such as by the use of a multi-coloured ribbon 13 or by modifying the appearance of the characters which is perceptible to the eye without impairing their legibility. When the operator depresses any one of the main keyboard keys 2 the typing is made in black, but as described in paragraph on case-shift operation, when a service key is depressed the signal is printed in capitals in red. If it is the small capitals key that has been depressed all the following letters will be typed in green and in the case of large capitals and lower case the following characters are in black. The depression of one of the lateral keys 3 the characters are printed in blue so that distinction between common symbols on the typewriter, e.g. hyphen and subtraction sign; opening and closing inverted commas; is made in the characterisation of that character on the record R and a difference is made in the perforation of the tape 10. Ink-ribbon mechanism. To effect the characterisation by giving symbols a different colour the ribbon 13 has four coloured tracks shifted by a mechanism 14 and shown on Fig. 5 under control of the distributer 214 from the keyboard. Leads 19 from the distributer are connected to an electro-mechanical device 72 which is connected to three solenoids 66-68 which shift three differently angled wedges 59-61 and so raise a ribbon holding comb 53 from a normal position to one of three others. Case-shift operation. The shifting of the type-basket or the platen is accomplished by an electromagnet and two switching arrangements (Fig. 4, not shown) having one connection to all keys of the service keyboard 4 other than the three shift keys 5, 6 and 7 for which there is a separate connection. When an impulse is received from a key other than the shift keys the switch arrangements operate the electromagnet (39), and the typebasket or platen is shifted so that the service signal is printed on the record R in capital letter and as soon as signal ceases the electromagnet is de-energised and normal lower-case position obtains. When the lower-case shift key is operated shifting still occurs so the sign for indicating lower-case is printed in capital letter and similarly the electro-magnet releases when the signal ceases. If the small or large capital shift keys are operated shifting occurs and is held in the shifted position. A subsequent operation of the lower-case shift key however, whilst allowing its sign to be printed in capital letter, makes the shift mechanism take up the lower-case position when the signal ceases. Auxiliary power type-action. The type-levers 37, Fig. 3, are impelled against the platen by a power roller 32 to which a serrated cam 29, rotatively mounted on a pivoted bar 24, is allowed to engage when an electromagnet 21 is operated. In the rest position the cam 29 has a hollowed portion facing the roller 32. Line-counting and marking. Each time the carriage and platen 201 reach the end of a carriage return movement, the number of the line is printed automatically at 301, Fig. 1, under control of a metering apparatus shown in Fig. 9 from which ten connecting lines 211 extend to the appropriate type-members. The meter comprises five wheels 91-95 corresponding to a five digit number and each has an insulating outside surface except for one-tenth of a circumference, which forms a contact for making a connection on a contact ring 120. When the carriage reaches the end of its carriage return travel a contact lever 112 is disconnected from an earth connection on a rod 108 attached to a wheel supporting member 97 and a contact 113 makes with contact 114 when the wheel 91 is in engagement with the contact ring 120 so that a circuit is made to print the requisite number in the units column. After all the digits have been printed the carriage advances to the next line and in the course of the travel in letterspace direction, and when the support 91 and wheels return to its starting position, a pin 104 on the support engages a helical part of the shaft 103, rotates it slightly, advances a ratchet wheel one step, and also advances the wheel 91. The other wheels 92-95 are dependent for advancement upon the wheel 91 as in ordinary serial numbering devices. Specification 771,551 - is referred to.