US1753495A - Typewriting machine - Google Patents

Description

Amig 8, 1930 I v H. F. BARDWELL. 1,753,495

TYPEWRITING MACHINE Filed Sept. 20, 1927 Patented Apr. 8,. 1,930

UNITED STATES. PATENT OFFICE HAROLD F. BARDWELL, OF ROCHESTER, NEW YORK, ASSIGNOR '.II'Ovl ELECTROMTIO' TYPEWRITERS, INC., OF-ROCHESTER, NEW YORK, A. CORPORATION OF NEW YORK 'iYPEwRITING MACHINE Application led September 20, 1927. Serial N'o. 220,813.

This invention relates to a typewriting machine provided with power operated mechanism for actuating the type bars, such mechanism operating under control of the usual manually operable keys.

For the purpose of tyfpling bulletins, the titles of cinematograph lms, etc., a typewriter is sometimes equipped with types of unusually large size, and the amount of force necessary to produce clear impressions from such types .makes it necessary to operate each type repeatedly, even when the machine is actuated by power mechanism. The object of the present invention is to equip a typewriter of this kind `with power mechanism, so constructed and arranged that it will automatically operate each type bar-a plurality of times in rapid succession upon each operation of the corresponding key.

To the foregoing end, the invention consists in the construction and arrangement of parts hereinafter described, as defined in the appended claims.

In the accompanying drawings, Fig. 1 is a side elevation, partly in section, showing the essential elements of a power operated typewriter embodying the present invention. Fig. 2 is a partial plan view of the same machine, and Figs. 3 and 4 are, respectively, an end elevation and a side elevation of one of the cam units embodied in the power mechanism.

In the illustrated embodiment of the invention the type bars 5 are of ordinary form and arrangement, and each bar is actuated, in the usual manner, through a bell crank lever 7. Each lever is connected, by a rod 8, with one of a series of cam levers 9. These cam levers are pivoted, in two ranks, on'pivots 10 engaging bearing members 12 fixed upon the frame of the machine. Between the depending arms of the cam levers a power roller 13 is-journalled, and this roller is rotated constantly, in the direction shown by the arrow in Fig. 1, by any suitable means.. An electric motor 14 is shown, diagrammatically, as connected with the roller for this purpose.-

Each cam lever 9 constitutes part of a cam unit such as is shown in Figs. 3 and il. it

.the bell crank lever.

the lower end of the cam lever a rotatable cam 15 is journalled, this cam having two lobes with serrated surfaces adapted to c0- operate frictionally with the surface of the power roller. The roller is preferably covered with rubber or some other yielding frictional material.

The cams are shown in their normal inactive position in Fig. 1, but it will be apparent that if any one of the cams vbe turned sutilciently vto bring one of its serrated lobes into engagement with the roller, the roller will then cause continued rotation of the cam, unless and until the cam is again arrested in one of its idle positions. The form of each cam lobev is such that a half rotation of the cam will first cause the cam lever to swing away from the roller and pull downwardly upon the corresponding rod 8, thus rocking the bell crank lever 7, to which it is attached, and swinging the type bar into engagement with the platen. The type bar is then returned to normal position by the action of gravity, assisted by a spring 16 attached to The operation of each cam is controlled by a detent lever 17 and a spring arm 18, both mounted on the same pivotal axis 19 between the two side members of the cam lever. The

spring arm cooperates with two pins 20 pro- Jecting from one side of the cam, and a spring 21, coiled about the hub of the spring arm, tends to swing the arm in a direction to press itr against one or the other of these pins. Accordingly, when the cam is in its inactive position the spring a'rm, by engagement with a pin20, tends to turn the cam in a direction to engage it with the power roller. Such rotation is normally prevented, however, by the detent lever, which is provided with two detents 22 and 23, arranged to cooperate with a stop lug 24 projecting from the marginal portion of the cam, as shown in Fig. 3.

The detent lever is controlled by connection with one of the key levers 25. These levers arepivoted on a rod 26 on the frame of the machine, and each lever has a depending arm with a forked end, this end embracing avlug 28 which projects laterally the particularly upper end of the corresponding detent lever l 17. The key is normally held in raised posi- .detent lever bac tion by meansof a. spring 27, and in this position the detent lever is held in the position shown in the drawings, with the stop lug 24 pressed against the detent 22 owing to the rotative effect of the spring arm against the lower of the two pins 20. When the key lever is depressed to cause operation of one of the type bars, the detent lever is swung away from the axis of the cam, thus releasing the stop lug from engagement with thedetent 22. The spring arm then partly rotates the cam, but this motion is arrested by engagement ofthestop lug with the detent 23, the cam still being `out of operative engagement with Ythe power roller. Upon the release of the key, however, the key lever is raisedby the s ring 27, thus swinging the to its original position. This causes the release of the stop lug 24 from the detent 23, whereupon a further turning movement of the cam, under the influence of the spring arm, causes it to engage the power roller and to be given a complete rotation thereby, this rotation being terminated by the reengagement of the stop lu'g with the detent 22. It will thus be seen that the type bar is actuated twice, owing to the two lobes of the cam, at each oper-` ation of the corresponding key, but that the motion of the type bar does not begin until the key has been not only depressed, but also released and permitted to rise.

It is desirable to provide the machine with automatic means for causing a feed movement of the carriage, after each character has been written. This result is commonly secured, in a typewriter of ordinary construction, by causing either the type bars or some parts moving with them to -operate upon a universal member of some sort connected with the carriage escapement. Such an arrangement is not practical without modification in the present machine, owing to the fact that the type bar is always operated twice in succession, and this would result in two feed movements.

In the present machine, the carriage feed or letter spacing-'movement is controlled through the usual manuell operable control member or spacer bar. hor this purpose all of the key levers are extended to the front of the machine,'and arranged to move in slots` in a guide and stop member 29.` A. spacer bar 30 is supported by the usual latm eral arms or levers 3l, which are shown, in li`ig..2 as integral with a cross bar 32, upon which thespacer bar is supported. This cross bar is provided, at its lower edge, with a flange 38, which .lies beneath the ends of all of thscharacter key levers. will be understand' that this spacer may control,

in the usual manner, a carriage escapement been not only depressed but also released, is i not essential to the invention. It is convenient, however, in 'connection with the feed controlling mechanism just described, since it affords time for the carriage feed, while the key is being depressed, so that this feed movement may be completed by the time the key has returned to normal position and caused the movement of the type bar. It'will be apparent that this arrangement results in a feed movement always preceding the first letter of a line of type, but this extra feed movement need causevno inconvenience, as it may readily be allowed for in the operation of the machine.

Theprecise form and construction of the power mechanism are not essential features of the present invention, andthe mechanism actually illustrated and described is used only for illustrative purposes. Such novel and patentable features as this mechanism contains are not claimed herein, as they consti` tute no part of the present invention'.

The invention claimed is:

1. In a typewritin machine the'combination, with a type an a keyof power-mechanism controlled by the key and connected with the type to actuate the latter, said mechanism comprising a power roller, a cam cooperative with the power roller and having a plurality of lobes, and detent-mechanism` connecting the key and the cam and arranged to permit a complete rotation of the cam at each depression and release of the key.l

2. In a typewriting machine, the combination o f a type, a key,` power mechanism for causing a plurality of operations of the type upon each cycle of movement of the key, and letter spacing mechanism for causing a single spacing movement upon each cycle of movement of the key.-

' HAROLD F. BARDWELL.

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