US2044550A - Typewriter - Google Patents

Description

G. TEISSEDRE TYPEWRITER Filed Feb. 16, 1932 2 Sheets-Sheet l c712 (ran for G. TEISSEDRE TYPEWRITER June 16, 1936.

Filed Feb. 16, 1932 2 Sheets-Sheet 2 iii c722 pen for m kw Z m Patented June 16, 1936 UNi'lEfi STATES TYPEWRITER Gustave Teissdre, Strausbourg-Alsace, France Application February 16, 1932, Serial No. 593,290 In Germany February 25, 1931 9 Claims.

Typewriter-systems of the kind hitherto in use may be divided into two principal groups, which may be referred to briefly as single-type and alphabetical-unit machines. Of these the former has, in the form of the single-shift type-bar machine, developed into what may be termed a standard-type, whilst the latter has practically disappeared.

The reason for this resides in a predominantly empirical development of the printing-mechanism, permitting only of sufficient writing-speed and percussive force by means of alternately actuated single-type bars. For this reason the type bar system, despite kinematic imperfections, still represents the most practical solution, while in the case of the alphabetical-unit system not only kinematic but also distinctly mass-kinematic difficulties remained to be overcome. Beyond this, in the case of the latter system, the double or even triple shift failed to keep pace with modern requirements.

In order, therefore, to open out in full effect the particular advantages of the alphabetical-unit system (simplicity, exchangeable type, and so on) the following conditions require to be fulfilled:

On the one hand increased writing-speed and ercussive force, and on the other hand extensive adaptation to the accepted standard-form, so that no necessity will exist for re-schooling in the mode of operating which has already acquired a refiectory character.

In consequence thereof the machine described in the following possesses a normal paper-roller with thoroughly visible front-stroke, single-shift universal keyboard, in short all of the outer constructional parts in the form and size of a standard-model.

On the other hand the total internal construction is carried out systematically in such fashion that all parts which are subject to appreciable strain are constructed and mounted accordingly, but at the same time the moment of inertia of all rapidly-moving parts is reduced to a mere fraction of that hitherto usual.

The primitive type-wheel, being a rigid body, permitted indeed of direct and fairly visible impression on normal paper-roller, but these advantages were outweighed by a moment of inertia of such extent that despite the use of ebonite or other light materials (that is, loss of percussive force), the writing-speed proved to be wholly insufficient. Objection was furthermore made to the fact that the wheel-drive alone was subject to the entire wear, which otherwise is distributed over perhaps 42 type-bars,--a fault which was also due to the size of the masses to be moved.

The type-shuttle device accordingly conformed to the double tendency towards reduction of mass and simplification of drive. The former resulted in the lamelliform type-carrier, sliding on a solid circular rail or anvil, and the latter in the segmental shape, Which, however, required a radius of such size, that the advantage obtained by reduction of the mass isv thoroughly counterbalanced by this second factor in the product mr In consequence thereof the force required can only be reduced by means of an additional recourse, namely by increased load on the carriage-mechanism, which, however, conforms just as little to actual requirements as the platenless rear-hammer device. Finally, the shuttle-motion, referring to the key-stroke, resulted in a particularity which will be treated of at a later point.

The present invention avoids all of these disadvantages by a remarkably simple solution. An essential feature of this invention is the use of a non-rigid, cylindrical type-carrier of minimum inertia, mounted on a rigid core-cylinder. The non-rigid type-jacket may, in consequence,'be as thin as paper Without the compression strength of the whole body being diminished. If now the same is provided on a beating-lever, it combines with the direct stroke of the type-wheel the ready movability of the type-shuttle, but this with the entirely new result that it is no longer m or r alone, but both together, which receive the lowest possible value, whereby mr drops from 5-7 to about .1 g. cmfi.

The basic fault of the primitive alphabeticalunits, namely, the loading of every single letter with the remaining 83-89 types in the form of actual dead-weight, is thereby practically eliminated, as the about sixtyfold movability of the new type-carrier (the movability being inversely proportional to the respective momenta) greatly exceeds the manually attainable writing-speed. Even more prominent is the fact that the moment of inertia of all 84 types hardly amounts to 1/140 of that of a single-type lever of the usual kind. Compared to the stroke of a single type, the force required by the type-jacket is consequently so minim, that it has no longer to be taken into account,which will disclose the full range of the present solution.

In further consequence of this minim mass, the possibility of wear will obviously also be diminished far beyond that of other systems hitherto known. Finally, it will be readily seen from the drawings that the arrangement of the beatinglever or type-carrier device leaves the line of writing completely visible and freely accessible, and also calls for merely a small slot in the coverplate of the casing, so that the mechanism is protected against eraser-dust, and other injuries, in a manner not attained heretofore.

The essence of the invention will be described with the assistance of a few possible forms of embodiment.

Fig. 1 is an elevation.

Fig. 2 is a plan-view of the machine according to the invention.

Fig. 3 shows a variation of the printing-movement according to Fig. 2.

Fig. 4 is a plan-view, corresponding to Fig. 2, of the machine according to Fig. 1, and shows the oscillating jacket-motion.

Fig. 5 details the movements of mechanism Fig. 4.

Figs. 6-8 show the shifting-device.

Figs. 9 and 10 are side-views of the frame,

Fig. 11 is a horizontal section showing the typewheel in printing relation with the platen.

The type-carrier consists of a cylindrical type-jacket I9, with a weight of about 1 gram and a radius of gyration of about 1 cm. (stamped,

.for instance, in .1 mm. sheet-steel or moulded in hard aluminium-alloy or synthetic resin), which forms a cylindrical-couple with the corecylinder 9, the latter acting as percussiveor as printing-body (alphabetical-unit).

Mounted in form of a front-striking type-bar, this body reaches, despite its extremely small angle of movement (about 20), an uncommonly high degree of acceleration,-combining this way with a minimum mr of the jacket, a maximum of the core, which fulfills the requirements set forth for the alphabetical-unit in respect of writing-speed and percussive force.

As the raising of the fine type-strokes has no perceptible influence on the momentum, the above-said radius of gyration (Tg in Fig. 11) practically coincides with that of the thin jacket itself, while the outer diameter D (or the corresponding circumference) results large enough to permit the arrangement, in 4 rows of 21 each, of a standard-set of 84 pica characters, the relatively strait spacing of which gets fully compensated by the high curvature of type-jacket I9, so that a simultaneous impression of neighboring characters on platen I2 does not more occur than in former three-rowed typewheels with larger spacing, but slighter curvature (see horizontal section, Fig. 11).

The impression-movement is shown in Figs.

(a) Stroke-system according to Figs. 1 and 2.The keys are divided into two groups, left and right. Transversely to each group there is disposed a shaft I, bearing a series of wings 2, 2', 2", and so on, in shape of rolling-levers. The two lower banks of keys, through the medium of rolling-thumbs 3, and the two upper banks, through the medium of rolling-cams 3, each actuatein pairs the appertaining rolling-levers, and thus impart accelerated motion to the lever 4 mounted at the end of shaft I. This motion is transmitted backwards by means of a connecting-rod 5, to a further rolling-lever 6 which, in the same manner as its counterpart I5 pertaining to the right-hand group of keys, rolls on the common lever I. The latter, through the medium of a drawing-wire 8, finally causes the stroke of the typeor alphabetical-unit bar 9,

rolling levers or cam motions precludes high leverages because at increasing rates of acceleration their inertia would increase geometrically to enormous values. The cooperation of multiple pairs under slight leverage reveals on the other hand the unforeseen effect that their total inertia, with the same rates of acceleration as before, increases merely arithmetically, and in practically. quite negligible proportions (ratio of progression =+2 instead of x24, for instance).

Thus the levers 2, 3 and 6, 'I if shaped for a slight initial leverage of about 1:3 and a corresponding final leverage of about 3:1 in each pair, will give an acceleration of roughly 1:9 per pair, and as product of both pairs about 1:80, as against an average of merely 1:4 in the former single-pair motions. Now the final 22 being the main factor of percussive power, not only is this factor thus raised from 16 to 6400, but the inertia resistance, instead of increasing correspondingly, remains much less than in the previous low-speed motions.

This extremely high 0 as previously mentioned, then enables the mass of the type carrier to be minimized (thin jacket, hollow c0re see Fig. '7) and a maximum writing speed and percussive power to be realized at once.

The above characteristics may be considered sufficient in practice, but obviously there is no objection to employing a larger number of pairs or other leverages consistent with the above statements.

There is thus obtained by simple means a very high 11 which in turn permits of the typecarrier mass, as well as the angle of movement a, being made correspondingly small without prejudice to the percussive force, whereby the writing-speed, (assisted by the low moment of inertia of the type-jacket drive described in the following), is increased in the same proportion.

(b) Silent printing-system according to Fig. 3.This device, hitherto applied to the thrustbar system only, may find a new and theoretically more correct application in connection with the strictly frontal stroke of the alphabetical-unit type-carrier, without the principle or execution of the latter suffering any alteration. The lever 4 then actuates, by means of drawingwire ID, the knee-jointed lever I I, and the latter the type-bar 9, whereby the alphabetical-unit is pressed against the paper-roller I2. The counter-bearing for the knee-lever II is constituted by a fiat-spring I3, which in the case of varying thickness of paper on the roller I2 automatically compensates the pressure, while in the case of multiple thrust-bars the adjustment necessary in accordance to the number of carbon-copies constitutes a disadvantage.

The oscillation of the jacket takes place in the following manner (Fig. 4)

Simultaneously with the type-bar stroke, the rolling-lever 6 (or B actuates by means of a drawing-wire I4 (or M a triangular rockinglever I5 pivoted at I6 to an auxiliary lever I5, which in turn is pivoted at I6 to the base plate 33. A pull on the wire I4 (Figs. 4 and 5b) swings the triangular rocking lever I5 about pivot lin and segment I1 is moved to the right by means of a pin secured to the top of I5. A pull on the wire W (Fig. 5d) causes [5 and [5 to swing together about pivot l6 and moves the'segment to the left, pinion l8 and type jacket l9, fixed on spindle 32 (Fig. '7), being oscillated accordingly. The return of rocking lever l5 and consequently of jacket 19 into the normal'position is performed in a manner known per se by draw springs linked near the corners of triangle IS, in opposition to the pull of the wires I4 and Ma respectively. This lever moves the toothed segment I1, and the latter, by means of the pinion IS, the type-jacket l9.

Since the angle of oscillation of the levers B and 6 in their function as stroke-elements is invariable, the excess motion thereof, respecting the different angles of oscillation of the typejacket between and 1 180, is taken up by a compensating- spring 20 or 20*, and that, as a result of the low inertia-value, without perceptible difference in the stroke of the different keys.

These compensating-springs accordingly permit of a further and very appreciable reduction of mass in the drive, owing to the omission of all particular adjustment-means, such as slotted sectors, proportional-levers, curve-rails and the like.

A considerable disadvantage of these parts in the systems hitherto known, also made itself apparent in such form that not until one key had entirely returned was it possible to depress another key, as otherwise the drive became locked. As set forth above, however, in connection with the type-bar system, a condition for speedy writing is, that during the return of one key the next one may already be depressed. This in the present case is permitted by the rocking-lever l and its auxiliary lever [5 which, upon simultaneous pull of the wires [4 and M acts as a differential device (Fig. 50) for such time until the first key has reached its zero-position (Fig. 5d).

Appreciable relief of the alphabetical-unit may furthermore be obtained by omission of the adjustmentor star-wheel, viz., by reason of an extremely simple device (Fig. 5e) The pivot of the toothed segment I! is not fixed, but is provided on a lever 2!, so that in the first place it may operate the pinion IS with slight clearance of the teeth, while the under arm 9b of the typecarrier support (Figs. 1 and '7) imparts to'lever 2|, through the medium of coupling-rod 2W, a slight motion by means of which, shortly prior to the impression, the segment gets forced into the teeth of the pinion, thus setting the position thereof and also of the type-jacket, without play, whereby even the central guiding in fork-, pinor other form, which has been found necessary in all front-stroke systems, is rendered wholly superfluous.

According to the above description, however, the rocking-lever would on each stroke impart to the type-jacket a complete oscillation out of the zero-position to or 180. To determine the particular letter it is accordingly necessary for each key to actuate a stop which fixes the segment l1, and through pinion 18 also the type-jacket IS, in the corresponding position. This occurs by coupling the segment with the light setting- pointers 22 and 22*- over both groups of keys (Fig. l). The exact position of these pointers is determined by stops 23, 23', 23", and so on, connected with the keys. The particular excess movement of the segmental-drive is, as stated above, taken over by the compensating- springs 20 and 20 The motion of stops 23, 23, 23 and so on (Figs. 1

and 4) is essentially the same as in the old typeshuttle system, their shift being merely oblique instead of vertical.

When thumb 3 (Fig. 1) moves upwards, stop 23, leaning against a pin 3" on the upper keylever, slides into the dotted position and hereby blocks pointer 22 as shown in Fig. 4, number 23'. The same result is obviously obtained, after Fig. 1, by the downward motion of supporting-pin 3", if the upper key-lever gets depressed.

In this connection each pair of keys conforms with a particular position of pointer or jacket, each second key, as described in the following, causing an automatic displacement of the jacket.

Shifting-device (Figs. 6-8) As a basic departure from all other type-wheel systems, this machine possesses the simple-shift, alone employed at the present time. In place of the three rows or groups of letters heretofore usual, there are provided on the type-jacket merely two groups, preferably divided into four rows, viz., small letters in rows I and II, capitals and figures in rows III and IV(Fig. 7). The two upper banks of keys cause direct impression of the type-row I, while the two lower banks of keys move row II into writing-position by shifting the type-jacket.

For this purpose each of the 2| lower keys is fashioned as an angle-lever (Figs. 1 and 6), the

arm 24 of which actuates a flap-like movable frame 25, mounted across the keyboard. The end of the frame-shaft bears a lever 26, which by means of connecting-rod 2?, angle-lever 23, drawing-wire 29 and angle-lever 38 transmits its motion as far as the hollow type-bar 9 (alphabeti- 1 cal-unit lever). In the latter there slides (Fig. '7) shiftable by means of angle-lever 3G to the extent of the height of a type-row, the sleeve 3| together with shaft 32 mounted therein, which shaft carries at the bottom the pinion l8, and at the top the exchangeable type-jacket i9.

Upon depression of the lower keys, the typejacket is accordingly lifted to row II. viz., also with so small an inertia-effect that no difference is perceptible in the key-stroke. It is this very unnoticeable requirement for force which permits of the types being divided into 2 x 2 rows, and accordingly of single-shifting at any writing-speed, something which heretofore did not seem compatible with the type-wheel system.

Independently of this automatic jacketdis-v placement to the. extent of one type-row, the proper shift is done by lifting the entire alphabetical-unit by the height of two rows, whereby the type-group III/IV is made to print in place of group 1/11. This is performed by the usual shiftkeys (Fig. 8) in such fashion, that the base-plate 33, supporting the alphabetic-unit and its settingmechanism, is moved up and. down between corresponding stops by means of two arms 3 and ti l on a commonshaft, and a parallel-guide 36.

In place of this method of actuating the baseplate. which conforms with the oscillatory typebasket, but is considerably lighter and more silent than any other operable form of actuation, the base-plate 33, with omission of the-parts 34-36, may be fixed on the frame, andtheshifting be performed in usual manner by vertical translation of the paper-roller, without the basic idea or the execution of the actual writing-mechanism suffering any alteration.

Frame: The constructional space (shaded in Fig. 9) amounts to only half of the usual parallelopiped, so that the two side walls may be divided diagonally and jointed along the edge AB of the casing proper. For purposes of transport the lower halves of said walls (white in Fig. 9) are folded inwards against the bottom of the casing, whereby the machine is reduced from the operative full-size of a standard model to that of a fiat portable-machine (Fig. 10). Since furthermore the casing, in addition to the key-slots, possesses only one small aperture for the typecarrier lever, the mechanism, as already mentioned, is protected in thorough fashion against eraser-dust, etc.

I claim:

1. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, means joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and printing key actuated means coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity.

2. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, means joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and at least two pairs of printing key actuated rolling levers coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity.

3. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, a linkage joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and printing key actuated means coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity.

4. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having the small letters disposed thereon in two upper circumferential rows and capital letters and other signs in two lower circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, means joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and printing key actuated means coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity. v

5. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a hollow core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, a linkage joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and two pairs of printing key actuated rolling levers coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity.

6. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation, a base plate, a type bar supporting at its upper end the said core cylinder, a pinion mounted on the lower end of the said type bar, a toothed segment engaging with the said pinion, a triangular rocking lever actuating the said segment, members connected with separate corners ofthe said rocking lever and actuated by the said printing keys, andprinting key actuated means coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity. Y

7. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon Which the jacket is mounted for rotation about its axis and for axial translation, a base plate, a type bar supporting at its upper end the said core cylinder, a pinion mounted on the lower end of the said type bar, a toothed segment engaging with the said pinion, a triangular rocking lever actuating the said segment, members connected with separate corners of the said rocking lever and actuated by the said printing keys, means for shifting the pivot of the said segment toward the said pinion shortly prior to the impression of the type on the platen for the purpose of eliminating play between the said segment and the said pinion, and printing key actuated means coacting to overcome quickly the inertia of the type carrier and to swing it against the platen with a high final velocity.

8. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier having small inertia comprising a cylindrical jacket having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation 180 left and right about its axis and for axial translation, a type bar carrying at its upper end the said core cylinder, a base plate, a spindle arranged slidably within the said type bar and carrying the said jacket, and at least two pairs of printing key actuated rolling levers coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final velocity.

9. A visible writing line typewriter comprising a four bank keyboard having shift keys and printing keys, a platen, a type-carrier comprising a sheet steel jacket having a moment of inertia of the order of approximately .1 grammes/square centimetre and having characters arranged thereon in four circumferential rows, a core cylinder upon which the jacket is mounted for rotation about its axis and for axial translation a distance equal to the distance between two adjacent rows of type, a base plate, means for supporting the core cylinder on the base plate for swinging motion toward the platen, means joining the shift keys and base plate for shifting it and the type-carrier a distance equal to that between the first and third rows of type, and printing key actuated means coacting to overcome quickly the inertia of the type-carrier and to swing it against the platen with a high final Velocity.

GUSTAVE TEISSEDRE.

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