Patent GB-190009811-A (GB)
Title: Improvements in or relating to Combined Typewriting and Computing Machines.
Inventor: BOULT ALFRED JULIUS
Filed: 1900-05-28
Granted: 1900-07-14
Abstract: 9811. Boult, A. J., [National Addograph Co.]. May 28. Type-writers.-Relates to a combined type-writing and computing machine which, while performing all the usual functions of a type-writer, is capable of adding a column of figures written by the type-writer. The construction is such that marks or characters, such as a comma separating hundreds from thousands, can be interspersed between the numerals without interfering with the computation. Fig. shows a sectional side elevation of the machine, and Fig. 2 a plan of the computing-mechanism. The type-writer is of well-known construction, comprising a carriage B, inking-ribbon Q, pivoted feed-rack b<2>, escapement E, universal bar E<1>, operating-levers C, type-bars D, and keys F. The computing-mechanism consists of a series of wheels G' to G<8>, Figs. 2 and 9, connected by wheels H<1> to H<7> and pawls h' so that, when a wheel, such as G<7>, is turned through 10 units, it adds 1 to the reading of the next wheel on the left. The figures recorded on the wheels G are read through windows K. Sliding upon fixed transverse rods N at the baseof the machine is a narrow frame M termed the " computer carriage." At the rear of this carriage is pivoted a lever O terminating in a toothed sector o' and normally held upwards by a spring o<2>. Above the lever O are a series of ten bails S<0> to S<9>, pivoted to the side bars R and nesting together in the manner shown in Fig. 2. The bails consist of tubes S carried by arms s'. In addition to the usual keys F, the keyboard is fitted with ten numeral-keys F<1>, to be used exclusively for printing numerals in the column of figures to be added. The stems V of these keys fork over operating-levers C for the type-bars, and extend downwards so as to act directly upon the bails, as in the case of the stem V<0>, or through the medium of levers U and links T. The extent to which the lever O is depressed depends upon the bail brought into action. If the bail S<9> is depressed, the sector o<1> will turn the wheel G through nine teeth, whereas the bail S' will only rotate it through a single tooth, and the bail S<0> will not depress the lever O sufficiently to rotate the wheel G at all. The wheels G are provided with detent pawls J, which prevent backward rotation ; the sector o<1> is therefore unable to rise after depression. The computer-carriage M is, however, under the control of an escapement which permits it to move to the right each time a key F' is depressed, and during this movement the sector o<1> escapes from the teeth of the wheel G, rises under the influence of the spring o<2>, and finally comes to rest vertically above the next wheel G to the right of that just actuated, the computer-wheels being thus rotated through the proper amounts in turn from left to right. The computer-carriage escapement consists of a pair of transverse bars W, W', Figs. 1 and 5, having on their front edges notches w, of which the distance apart is that of two consecutive wheels G. The lower bar W is fixed ; the upper one is capable of a limited right-hand movement against the tension of a spring w<3>. A lever I, pivoted at the rear of the computer-carriage, bears an escapement pawl i<1> normally in engagement with the upper bar W<1>. Pins i<3> on the bar 1 project into the path of the bails S (including the bail S<0>), so that the depression of any of the keys F<1> will engage the pawl i<1> with a notch in the lower bar W. The spring w<3> moves the bar W<1> to the left, the pawl w<1> engaging with the next notch when the lever I rises. The main driving-spring of the carriage M then opposes the spring w<3>, and draws the carriage one step to the right. A blank key is provided which operates both the computer and typewriter escapements without printing any character on the paper. When the computer-carriage is moved to the extreme right, its levers will be operated idly, and the type-writer can be used in the usual way. The carriage is returned to the left-hand computer-wheel by means of a rod m<4>, Fig. 2. To ensure that the lever O shall always be properly depressed, each bail carries a ratchet-pawl Z, Fig. 7, which moves round a stationary elliptical ratchet-block Z<1>, carried by the plate a<1> of the frame. A pin b<3> is provided on the rack-bar of the type-writer carriage, which, when the bar is tilted to release the escapement, moves into the path of a fixed stop l<1>, and thus enables the carriage to be rapidly brought back to the column alignment. Fig. 12 shows a series of computing-wheels adapted for adding English money. The wheels G<11> for the pounds column are of the ordinary decimal type. The wheel G'‹ for the shillings column is provided with numbers from 1 to 20, which is represented by 00. It bears two series of teeth g<5>, g<4>, which are acted upon in turn by the sector o<1>. Devices are provided by which, if the numeral key denominated 1 is depressed while the sector o<1> is over the teeth g<5>, the wheel G<10> will be turned through ten spaces instead of one. If, however, the same key is depressed when the sector is over the teeth g<4>, the wheel will only turn through one space. Thus, in printing the numeral 11 in the shillings column, the printing of the first 1 registers ten shillings and the printing of the second brings the register to eleven. The wheel for the pence column is operated in a like manner.